HomeTopicsInequalities & GraphingGraphing Linear Inequalities
Back to all topics

Inequalities & Graphing

Graphing Linear Inequalities

Graph a linear inequality by first graphing the boundary line (solid for ≤ or ≥, dashed for < or >), then shading the region that satisfies the inequality.

Solid line means "included," dashed means "not included" — then just test a point to know which side to shade!

Visualize It

Boundary line + shaded region

y=x−1xy-8-8-6-6-4-4-2-2224466880

Watch & Learn

Watch a clear, friendly video explanation of Graphing Linear Inequalities:

Watch on YouTube →

Opens a YouTube search for the best tutorial videos on this topic.

Worked Examples

Follow along with these step-by-step examples. Take your time — there's no rush!

1Example 1

Problem

Graph y > 2x − 1

Step-by-Step Solution

1

Graph the boundary line y = 2x − 1 as a DASHED line (> means not equal).

2

Test point (0, 0): Is 0 > 2(0) − 1? Is 0 > −1? YES.

3

Shade the region containing (0, 0) — above the line.

Answer

Dashed line y = 2x − 1, shade above

y > 2x − 1 (shade above dashed line)

y=2x−1xy-8-8-6-6-4-4-2-2224466880(0,0)✓
2Example 2

Problem

Graph y ≤ −x + 4

Step-by-Step Solution

1

Graph y = −x + 4 as a SOLID line (≤ means equal is included).

2

Test (0, 0): Is 0 ≤ −0 + 4? Is 0 ≤ 4? YES.

3

Shade the region containing (0, 0) — below the line.

Answer

Solid line y = −x + 4, shade below

y ≤ −x + 4 (shade below solid line)

y=−x+4xy-8-8-6-6-4-4-2-2224466880(0,0)✓
3Example 3

Problem

Graph y ≥ 3

Step-by-Step Solution

1

Graph the horizontal line y = 3 as a SOLID line.

2

Shade above the line (all y values ≥ 3).

Answer

Solid horizontal line at y = 3, shade above

y ≥ 3 (shade above y = 3)

y=3xy-8-8-6-6-4-4-2-2224466880
4Example 4

Problem

Graph y < x

Step-by-Step Solution

1

Graph y = x as a DASHED line (strict inequality).

2

Test (1, 0): Is 0 < 1? YES.

3

Shade the region below the line containing (1, 0).

Answer

Dashed line y = x, shade below

y < x (shade below dashed line)

y=xxy-8-8-6-6-4-4-2-2224466880(1,0)✓
5Example 5

Problem

Graph y ≥ −2x + 1

Step-by-Step Solution

1

Graph y = −2x + 1 as a SOLID line (≥ includes equal).

2

Test (0, 0): Is 0 ≥ −2(0) + 1? Is 0 ≥ 1? NO.

3

Shade the region NOT containing (0, 0) — above the line.

Answer

Solid line y = −2x + 1, shade above

y ≥ −2x + 1 (shade above solid line)

y=−2x+1xy-8-8-6-6-4-4-2-2224466880(0,0)✗

Your Turn — Practice Problems

Try all 5 problems on your own first. Write out your work — that's how it sticks!

💡 Tip: Don't peek at the answers until you've genuinely tried each one.

1

Is the boundary line solid or dashed for y < x + 2?

2

Is the boundary line solid or dashed for y ≥ 3x?

3

Test (0,0) in y > x − 5. Is it in the solution region?

4

For y ≤ 2x + 1, do you shade above or below the line?

5

For y > −2x + 3, do you shade above or below?

6

Test (2, 5) in y > 2x − 1. Is it in the solution region?

7

Is the boundary line solid or dashed for y ≤ −x?

8

For y < x + 4, test (0, 0). Is it a solution?

9

For y > 3x − 2, test (0, 0). Is it a solution?

10

For y ≤ x − 5, test (0, 0). Is it a solution?

11

What is the first step when graphing a linear inequality?

12

For y ≥ 2x + 1, do you shade above or below?

Finished all 12? Give yourself a pat on the back — then check your work!

Keep going — you're on a roll!

Every topic you master is another step on your journey.

Explore More Topics