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Quadratic Inequality Calculator

Name: Quadratic Inequality Calculator
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Solve any quadratic inequality instantly — get step-by-step solutions, parabola graphs, number line visualization, and interval notation. Free, no sign-up required.

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Why this page is different

Built specifically for quadratic intent instead of reusing a generic inequality layout.

Pairs root-based interval logic with a parabola graph and a number line on the same page.

Explains double roots, no-real-root cases, and downward-opening parabolas instead of hiding them behind a login.

Quadratic Solver

Built for quadratic inequalities with roots, sign analysis, parabola visualization, interval notation, and quick value verification.

Enter a quadratic inequality

Live parse preview

x^2 - 5x + 6 > 0

Supported Input Styles

x^2-5x+6>0 solves a standard-form quadratic.
x^2-4<0 highlights a middle interval between two roots.
2x^2+x-3>=0 keeps boundary roots because the symbol is inclusive.
-x^2+4x-3>0 flips the sign pattern because the parabola opens downward.
x^2>9 is rearranged into standard form automatically.

Math Keyboard

Tap powers, symbols, and constants for fast quadratic-inequality input.

Result

The quadratic solution set is shown below in notation and on the number line.

Rootsx_1 = 2,\; x_2 = 3

Interval(-∞, 2) ∪ (3, ∞)

OpensUpward

Standard form

x^{2} - 5x + 6 > 0

Discriminant

\Delta = 1

Roots

x_1 = 2,\; x_2 = 3

Opening

Opens Upward (a > 0)

Factor view

(x - 2)(x - 3)

Step 1

Move all terms to one side

Rewrite the inequality as a quadratic compared with zero.

Before

x^{2}-5x+6 > 0

After

x^{2} - 5x + 6 > 0

Step 2

Find the critical points

The real roots split the number line into intervals where the quadratic keeps a constant sign.

Before

x^{2} - 5x + 6 > 0

After

x = 2,\; 3

Step 3

Choose the intervals with the correct sign

Because the parabola opens upward, it is positive outside the roots and negative between them.

Watch the endpoint logic carefully. Strict inequalities exclude roots, inclusive inequalities keep them, and repeated roots do not create a sign flip.

Interval	Test value	f(x)	Factor signs	Sign	Keep?
x < 2	$1$	$2$	- , -	+	Yes
2 < x < 3	$2.5$	$-0.25$	+ , -	-	No
x > 3	$4$	$2$	+ , +	+	Yes

Because the parabola opens upward, the wanted sign appears outside the two roots.

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Solve absolute value inequalities with case splitting, interval notation, and step-by-step explanations.

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How to Use the Quadratic Inequality Calculator

This quadratic inequality calculator is designed for the patterns students actually meet in algebra: standard-form inequalities like x^2 - 5x + 6 > 0, rearrangement problems like x^2 > 9, repeated-root cases such as x^2 + 2x + 1 <= 0, and downward-opening parabolas such as -x^2 + 4x - 3 > 0. You can type directly into the expression box or switch to coefficient mode when you want to think in terms of a, b, c, and the comparison sign.

After the input is parsed, the page keeps the workflow compact and visual. The Steps tab explains how the quadratic is rewritten, how the roots are found, and why the sign is chosen on each interval. The Parabola Graph tab translates that same reasoning into a curve on the coordinate plane, while the Number Line and Interval Notation tabs convert the same answer into the standard classroom representations.

If you are learning the topic for the first time, use the tabs in order: Steps, Parabola Graph, Number Line, then Interval Notation. That sequence mirrors how strong algebra students think. First identify the structure, then locate the critical x-values, then read the sign of the quadratic, and finally compress the answer into symbols. If you are only checking homework, jump straight to the Verify tab and test a few values from inside and outside the reported intervals.

Enter a quadratic inequality such as x^2 - 5x + 6 > 0 or switch to coefficient mode for ax^2 + bx + c comparisons.

Review the steps to see the standard form, discriminant, roots, sign chart logic, and interval decision.

Use the parabola graph, number line, interval notation, and verify tabs to confirm the answer from several viewpoints.

What Is a Quadratic Inequality?

A quadratic inequality compares a second-degree expression with zero or with another expression. In standard form it looks like ax^2 + bx + c > 0, ax^2 + bx + c < 0, ax^2 + bx + c >= 0, or ax^2 + bx + c <= 0. Because the variable is squared, the graph is a parabola rather than a line, and the solution is usually an interval or a union of intervals instead of a single number.

This is the main difference between a quadratic equation and a quadratic inequality. A quadratic equation asks where the parabola meets the x-axis. A quadratic inequality asks where the parabola sits above the x-axis, below it, touches it, or includes the touching points. That is why a quadratic inequality solution is better understood as a sign pattern on the real line rather than as a list of roots only.

The parabola gives the intuition. If the graph opens upward, the quadratic is usually positive outside its real roots and negative between them. If the graph opens downward, that pattern reverses. When there are no real roots, the sign never changes at all. That single observation explains why some quadratic inequalities have two outer intervals, some have one middle interval, some have all real numbers, and some have no solution.

Quadratic equation

x^2 - 5x + 6 = 0

Quadratic inequality

x^2 - 5x + 6 > 0

Comparison point	Quadratic equation	Quadratic inequality
Goal	Find the x-values where the quadratic equals zero.	Find every x-value where the quadratic has the required sign.
Typical answer	One or two roots, or no real roots.	One interval, two intervals, all real numbers, a single point, or no solution.
Graph reading	Focus on x-intercepts only.	Focus on where the parabola lies above or below the x-axis.
Reasoning tool	Factoring or the quadratic formula is often enough.	You still find roots, but then you must read the sign pattern across intervals.

How to Solve Quadratic Inequalities Step by Step

Quadratic inequalities combine root-finding with sign-reading. The hard part is not only finding where the expression equals zero. The hard part is deciding on which intervals the quadratic is positive, negative, nonnegative, or nonpositive. The four methods below cover the most common solving strategies, and the sign-reference table under them compresses the patterns you need most often.

Factor Method

When the quadratic factors cleanly, this is the fastest route. Write the inequality in standard form, factor the quadratic, read the roots, and then decide whether the correct sign appears between the roots or outside them.

1.Move all terms to one side so the right side is 0.

2.Factor the quadratic expression if possible.

3.Set each factor equal to 0 to find the roots.

4.Use the opening direction and the sign requested by the inequality to select the valid intervals.

Example

x^2 - 5x + 6 > 0 \Rightarrow (x-2)(x-3) > 0

Sign Chart Method

This is the most reliable general-purpose method. Even when the quadratic does not factor nicely, the real roots still split the number line into intervals. You only need one test value from each interval because the sign of a quadratic cannot change without crossing a root.

1.Find the real roots using factoring or the quadratic formula.

2.Place those roots on a number line to form intervals.

3.Test one x-value from each interval or use parabola direction logic.

4.Keep the intervals where the sign matches the inequality.

Example

2x^2 + x - 3 \ge 0

Graphical Method

Graph the parabola y = ax^2 + bx + c and read the answer from the x-axis. If the inequality asks for > 0 or >= 0, keep the x-values where the graph is on or above the axis. If the inequality asks for < 0 or <= 0, keep the x-values where the graph is on or below the axis.

1.Sketch or compute the vertex and opening direction.

2.Mark any x-intercepts if they exist.

3.Read where the graph sits above, below, or on the x-axis.

4.Translate that picture into interval notation.

Example

x^2 - 4 < 0

Completing the Square

When factoring is awkward, completing the square reveals the vertex form and makes special cases easier to see. It is especially useful for repeated roots and for quadratics with no real roots.

1.Rewrite ax^2 + bx + c in or near vertex form.

2.Read the horizontal shift and vertical shift.

3.Use the vertex and opening direction to decide when the expression can be positive or negative.

4.Convert the visual conclusion into intervals or a special-case answer.

Example

x^2 + 2x + 1 = (x+1)^2

Case	a > 0	a < 0
$\Delta > 0,\; x_1 < x_2,\; \text{want } > 0$	$(-\infty, x_1) \cup (x_2, \infty)$	$(x_1, x_2)$
$\Delta > 0,\; x_1 < x_2,\; \text{want } < 0$	$(x_1, x_2)$	$(-\infty, x_1) \cup (x_2, \infty)$
$\Delta = 0,\; x = x_0,\; \text{strict sign}$	$x \ne x_0 \text{ for } > 0$	$x \ne x_0 \text{ for } < 0$
$\Delta = 0,\; x = x_0,\; \text{inclusive sign}$	$\mathbb{R} \text{ for } \ge 0,\; \{x_0\} \text{ for } \le 0$	$\{x_0\} \text{ for } \ge 0,\; \mathbb{R} \text{ for } \le 0$
$\Delta < 0$	$\mathbb{R} \text{ for } > 0 \text{ or } \ge 0;\; \varnothing \text{ for } < 0 \text{ or } \le 0$	$\varnothing \text{ for } > 0 \text{ or } \ge 0;\; \mathbb{R} \text{ for } < 0 \text{ or } \le 0$

Quadratic Inequality Examples with Solutions

These examples were chosen to cover the patterns that matter most in practice: two roots with outer intervals, two roots with a middle interval, a non-monic quadratic, a downward-opening parabola, a repeated root, an always-true case, a no-solution case, and an inequality that must be rewritten before solving. Taken together, they provide a full tour of the topic.

Example 1Basic factoring

x^{2}-5x+6 > 0

This is the standard outer-interval case. The parabola opens upward and has two real roots, so positive values appear outside the roots.

Two distinct roots, upward opening, strict positive inequality.

Standard form

x^{2} - 5x + 6 > 0

Discriminant

\Delta = 1

Roots

x_1 = 2,\; x_2 = 3

Interval answer

(-\infty, 2) \cup (3, \infty)

Move all terms to one side

Rewrite the inequality as a quadratic compared with zero.

x^{2} - 5x + 6 > 0

Find the critical points

The real roots split the number line into intervals where the quadratic keeps a constant sign.

x = 2,\; 3

Choose the intervals with the correct sign

Because the parabola opens upward, it is positive outside the roots and negative between them.

Set notation

\{ x \mid x < 2 \text{ or } x > 3 \}

Sign summary

Because the parabola opens upward, the wanted sign appears outside the two roots.

Example 2Middle interval

x^{2}-4 < 0

The parabola still opens upward, but now the inequality wants negative values. That means the solution is the interval between the two roots.

Difference of squares and a middle open interval.

Standard form

x^{2} - 4 < 0

Discriminant

\Delta = 16

Roots

x_1 = -2,\; x_2 = 2

Interval answer

(-2, 2)

Move all terms to one side

Rewrite the inequality as a quadratic compared with zero.

x^{2} - 4 < 0

Find the critical points

The real roots split the number line into intervals where the quadratic keeps a constant sign.

x = -2,\; 2

Choose the intervals with the correct sign

Because the parabola opens upward, it is positive outside the roots and negative between them.

Set notation

\{ x \mid -2 < x < 2 \}

Sign summary

Because the parabola opens upward, the wanted sign appears between the two roots.

Example 3Leading coefficient not equal to 1

2x^{2}+x-3 \ge 0

This example shows that the same sign logic still works when the leading coefficient is not 1. The inclusive symbol keeps the boundary roots in the final answer.

Closed endpoints and non-monic quadratic.

Standard form

2x^{2} + x - 3 \ge 0

Discriminant

\Delta = 25

Roots

x_1 = \frac{-3}{2},\; x_2 = 1

Interval answer

(-\infty, -1.5] \cup [1, \infty)

Move all terms to one side

Rewrite the inequality as a quadratic compared with zero.

2x^{2} + x - 3 \ge 0

Find the critical points

The real roots split the number line into intervals where the quadratic keeps a constant sign.

x = -1.5,\; 1

Choose the intervals with the correct sign

Because the parabola opens upward, it is positive outside the roots and negative between them.

Set notation

\{ x \mid x \le -1.5 \text{ or } x \ge 1 \}

Sign summary

Because the parabola opens upward, the wanted sign appears outside the two roots.

Example 4Downward-opening parabola

-x^{2}+4x-3 > 0

A negative leading coefficient flips the familiar sign picture. The quadratic is positive between the roots and negative outside.

Leading coefficient negative, so the sign pattern reverses.

Standard form

-x^{2} + 4x - 3 > 0

Discriminant

\Delta = 4

Roots

x_1 = 3,\; x_2 = 1

Interval answer

(1, 3)

Move all terms to one side

Rewrite the inequality as a quadratic compared with zero.

-x^{2} + 4x - 3 > 0

Find the critical points

The real roots split the number line into intervals where the quadratic keeps a constant sign.

x = 1,\; 3

Choose the intervals with the correct sign

Because the parabola opens downward, it is negative outside the roots and positive between them.

Set notation

\{ x \mid 1 < x < 3 \}

Sign summary

Because the parabola opens downward, the wanted sign appears between the two roots.

Example 5Repeated root

x^{2}+2x+1 \le 0

This quadratic is a perfect square. The graph only touches the x-axis once, so the inclusive inequality keeps the touching point as a single-point solution.

Discriminant zero and single-point answer.

Standard form

x^{2} + 2x + 1 \le 0

Discriminant

\Delta = 0

Roots

x = -1

Interval answer

[-1, -1]

Move all terms to one side

Rewrite the inequality as a quadratic compared with zero.

x^{2} + 2x + 1 \le 0

Find the critical points

The quadratic touches the x-axis at one repeated root.

x = -1

Use the repeated-root sign pattern

A positive-leading quadratic is nonnegative everywhere and equals zero only at the repeated root.

Set notation

\{ x \mid x = -1 \}

Sign summary

A double root does not flip the sign of the quadratic. The parabola touches the x-axis and leaves in the same direction.

Double Root: The parabola only touches the x-axis at x = -1, so the inclusive inequality keeps that single point and nothing else.

Example 6All real numbers

x^{2}+x+1 > 0

The discriminant is negative and the parabola opens upward, so the graph never crosses the x-axis and stays positive for every real x.

No real roots and an always-true inequality.

Standard form

x^{2} + x + 1 > 0

Discriminant

\Delta = -3

Roots

\text{No real roots}

Interval answer

(-\infty, \infty)

Move all terms to one side

Rewrite the inequality as a quadratic compared with zero.

x^{2} + x + 1 > 0

Check the discriminant

The discriminant is negative, so the quadratic has no real roots and keeps the same sign for every real x.

\Delta = -3 < 0

Use the sign of the leading coefficient

Because the leading coefficient is positive, the quadratic satisfies the inequality for all real x.

Set notation

\mathbb{R}

Sign summary

With no real roots, the sign of the quadratic never changes. The leading coefficient alone tells you whether the parabola stays above or below the x-axis.

All Real Numbers: The parabola opens upward and never crosses the x-axis, so the inequality stays true for every real x.

Example 7No solution

x^{2}+x+1 < 0

This uses the same quadratic as the previous example, but asks for a negative sign that never appears on the real line.

No real roots and an impossible sign request.

Standard form

x^{2} + x + 1 < 0

Discriminant

\Delta = -3

Roots

\text{No real roots}

Interval answer

\varnothing

Move all terms to one side

Rewrite the inequality as a quadratic compared with zero.

x^{2} + x + 1 < 0

Check the discriminant

The discriminant is negative, so the quadratic has no real roots and keeps the same sign for every real x.

\Delta = -3 < 0

Use the sign of the leading coefficient

Because the leading coefficient is positive, the quadratic never satisfies the inequality on the real line.

Set notation

\varnothing

Sign summary

With no real roots, the sign of the quadratic never changes. The leading coefficient alone tells you whether the parabola stays above or below the x-axis.

No Solution: The parabola stays entirely above the x-axis, so the requested sign never occurs.

Example 8Needs rearrangement first

x^{2}-3x \ge 10

The inequality is not in standard form yet. Moving every term to one side reveals the actual quadratic whose sign must be studied.

Standard-form rewrite before solving.

Standard form

x^{2} - 3x - 10 \ge 0

Discriminant

\Delta = 49

Roots

x_1 = -2,\; x_2 = 5

Interval answer

(-\infty, -2] \cup [5, \infty)

Move all terms to one side

Rewrite the inequality as a quadratic compared with zero.

x^{2} - 3x - 10 \ge 0

Find the critical points

The real roots split the number line into intervals where the quadratic keeps a constant sign.

x = -2,\; 5

Choose the intervals with the correct sign

Because the parabola opens upward, it is positive outside the roots and negative between them.

Set notation

\{ x \mid x \le -2 \text{ or } x \ge 5 \}

Sign summary

Because the parabola opens upward, the wanted sign appears outside the two roots.

Graphing Quadratic Inequalities on a Number Line

A quadratic inequality graph on a number line starts with the roots, because those are the only places where the sign can change. Two distinct roots create three intervals. A repeated root creates two outer intervals but no sign flip at the touching point. No real roots create no interval breaks at all, so the sign remains constant across the whole number line.

The number line is the bridge between algebra and interval notation. Once you know whether the quadratic is positive or negative on each interval, the graph becomes immediate: highlight the valid regions, use open circles for strict inequalities, and use closed circles when the endpoints are included. The same visual pattern then becomes interval notation with parentheses, brackets, unions, or the empty set symbol.

Parabola Graph

The purple curve is the full quadratic. The green overlays show the x-values and curve segments that satisfy the inequality.

Opening

Opens Upward (a > 0)

Vertex

(2.5, -0.25)

Roots

2, 3

Visible X Range

-2.5 to 5.5

Full parabola

Solution region

Vertex / verification marker

The highlighted x-values satisfy x^{2}-5x+6 > 0. Hover the curve to inspect coordinates, and drag horizontally to pan the graph.

Current x-span: 8

Number Line

Drag to pan. Use the controls or mouse wheel to zoom the view.

Open circles exclude endpoints. Closed circles include them.Export the current graph as SVG or PNG.

Endpoint rule

Use open circles when the inequality is strict and closed circles when the root should be kept. That endpoint choice must match both the interval notation and the algebraic sign.

Interval Notation for Quadratic Inequalities

Interval notation for quadratic inequalities can describe a middle interval, two outer intervals, a single point, the whole real line, or no solution. That is why quadratic problems are richer than linear ones. You are not only deciding left or right. You are deciding among several different answer shapes that depend on roots, opening direction, and whether the inequality is strict or inclusive.

A good check is to read the interval aloud before you move on. For example, (-infinity, 2) union (3, infinity) means every x less than 2 or greater than 3, with both roots excluded. By contrast, [2, 3] means every x from 2 to 3 including both endpoints. If your spoken interpretation does not match the graph, the interval notation needs to be corrected.

Solution shape	Example	Interval notation	Set notation	Meaning
Two outer open intervals	$x < 2 \text{ or } x > 3$	$(-\infty, 2) \cup (3, \infty)$	$\{x \mid x < 2 \text{ or } x > 3\}$	Strict sign outside two roots.
Middle open interval	$2 < x < 3$	$(2, 3)$	$\{x \mid 2 < x < 3\}$	Strict sign between two roots.
Middle closed interval	$2 \le x \le 3$	$[2, 3]$	$\{x \mid 2 \le x \le 3\}$	Inclusive sign between two roots.
All real numbers	$\text{all real } x$	$(-\infty, \infty)$	$\mathbb{R}$	The quadratic keeps the desired sign everywhere.
No solution	$\text{none}$	$\varnothing$	$\varnothing$	The required sign never appears on the real line.
Single-point solution	$x = 2$	$\{2\}$	$\{2\}$	A repeated root is kept only by the inclusive inequality.

Special Cases: No Solution & All Real Numbers

No Solution

Negative discriminant and the requested sign never occurs.

When the quadratic has no real roots, the graph never crosses the x-axis. If it stays entirely above the axis and the inequality asks for a negative value, there is no real x to keep. The same idea works in reverse for a downward-opening parabola that stays below the axis.

Example

x^2 + 1 < 0

Outcome

\varnothing

All Real Numbers

Negative discriminant and the parabola always has the requested sign.

If a parabola opens upward and never meets the x-axis, then it is always positive. That makes inequalities like x^2 + 1 > 0 true for every real number. A downward-opening parabola with no real roots behaves the same way for negative inequalities.

Example

x^2 + 1 > 0

Outcome

\mathbb{R}

Double Root

Discriminant equals zero, so the parabola only touches the x-axis.

A repeated root is not a normal sign change. The graph touches the axis and turns around, so the sign on both sides is the same. That is why strict inequalities can exclude only the touching point, while inclusive inequalities may keep just that point or keep the entire real line depending on the opening direction.

Example

x^2 - 4x + 4 \le 0

Outcome

\{2\}

Frequently Asked Questions

What is a quadratic inequality?

A quadratic inequality compares a second-degree expression such as ax^2 + bx + c with zero or another expression using <, >, <=, or >=. Its solution is usually a set of intervals rather than one single value.

What is the difference between a quadratic equation and a quadratic inequality?

A quadratic equation asks where the expression equals zero, while a quadratic inequality asks where the expression is positive, negative, nonnegative, or nonpositive. Equations focus on roots; inequalities focus on sign across intervals.

What does the solution of a quadratic inequality represent?

It represents every real x-value that makes the comparison true. On a graph, that means the x-values where the parabola lies above, below, or on the x-axis depending on the inequality symbol.

What is the standard form of a quadratic inequality?

The standard form is ax^2 + bx + c compared with 0, such as ax^2 + bx + c > 0. Writing the inequality this way makes it much easier to read roots, discriminant, and sign patterns.

How do you solve a quadratic inequality step by step?

Write the inequality in standard form, find the real roots of the corresponding equation, split the number line into intervals, determine the sign of the quadratic on each interval, and keep the intervals that satisfy the inequality.

How do you solve a quadratic inequality by factoring?

Move everything to one side, factor the quadratic if possible, find the roots from the factors, then use the roots and the opening direction of the parabola to decide which intervals satisfy the sign.

How do you solve a quadratic inequality using a sign chart?

Place the real roots on a number line, choose one test value from each interval, determine the sign of the quadratic on that interval, and keep the intervals where the sign matches the inequality.

How do you solve a quadratic inequality graphically?

Graph y = ax^2 + bx + c and read where the parabola is above or below the x-axis. Above the axis corresponds to positive values; below the axis corresponds to negative values.

How do you solve a quadratic inequality with a negative leading coefficient?

The method is the same, but the sign pattern reverses because the parabola opens downward. With two real roots, positive values occur between the roots and negative values occur outside them.

What happens when the discriminant is negative in a quadratic inequality?

A negative discriminant means there are no real roots, so the sign of the quadratic never changes. The answer is either all real numbers or no solution depending on the leading coefficient and the requested sign.

What is a double root in a quadratic inequality?

A double root occurs when the discriminant is zero. The parabola touches the x-axis at one point and turns around, so the sign on both sides stays the same.

Can a quadratic inequality have no solution?

Yes. If the parabola never reaches the required sign on the real line, the solution set is empty. For example, x^2 + 1 < 0 has no real solution.

Can a quadratic inequality have all real numbers as solution?

Yes. If the quadratic always has the requested sign, every real number works. For example, x^2 + 1 > 0 is true for all real x.

How do you solve a quadratic inequality with fractions or decimals?

You can solve it the same way after rewriting the inequality in standard form. Clearing denominators or working carefully with decimal coefficients still leads to roots, intervals, and sign analysis.

How does the parabola relate to the solution of a quadratic inequality?

The parabola shows exactly where the quadratic is positive, negative, or zero. The solution is the set of x-values where the graph lies in the region required by the inequality.

What does it mean when the parabola opens upward vs. downward?

Opening upward means the leading coefficient is positive and the graph eventually rises on both ends. Opening downward means the leading coefficient is negative and the graph eventually falls on both ends.

How do you graph a quadratic inequality on a number line?

Find the roots first, mark them as open or closed endpoints depending on whether the inequality is strict or inclusive, and shade the intervals where the quadratic has the correct sign.

How do you write the solution in interval notation?

Use parentheses for excluded endpoints and brackets for included endpoints. Split answers use a union, all real numbers use (-infinity, infinity), and no solution uses the empty set symbol.

What is the difference between open and closed intervals in quadratic inequalities?

Open intervals exclude the roots and are used with strict inequalities like > or <. Closed intervals include the roots and are used when the inequality is >= or <= and the roots belong to the solution.

How do I use this quadratic inequality calculator?

Type a quadratic inequality or switch to coefficient mode, press Solve, then review the steps, parabola graph, number line, interval notation, and verify tools. Example buttons are included if you want to start with a standard classroom problem.

Does this calculator show steps for quadratic inequalities?

Yes. The calculator shows the standard form, roots, opening direction, sign-chart reasoning, interval decision, and final notation.

Is this quadratic inequality calculator free?

Yes. The calculator, graphing tools, interval notation, and explanatory content are available without a sign-up.

Zone 6

Related calculators for the next step

Quadratic work naturally leads into linear review, absolute-value inequalities, compound logic, and graphing practice. These related pages keep the same design language but focus on different inequality patterns and answer shapes.

Linear Inequality Calculator

Solve one-variable linear inequalities with steps, interval notation, and a clean number-line graph.

Absolute Value Inequality Calculator

Solve absolute value inequalities with case splitting, interval notation, and step-by-step explanations.

Compound Inequality Calculator

Solve compound inequalities with interval intersection, union logic, and graph output.

Graphing Inequalities Calculator

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