Home/Integrated Math 1/Lesson 59

Slope-intercept form: write an equation from a graph

Read slope and intercept from a graph and write y = mx + b.

Do this: Read the concept below, then try the quiz or activity.

Lesson 59 of 192

30%

Concept

Objective: Students will derive slope-intercept equations from graph information.

Estimated Time: 12 minutes

Standards:

HSA-CED.A.2HSF-IF.C.7

Find b where the line crosses the y-axis, then compute m from any two points. Substitute into y = mx + b.

Try it

A line crosses the y-axis at 3 and passes through (2,7). Write its equation.

📈 Coordinate Grapher

Extract slope/intercept from the graph and test your equation.

TypeInequalityZoom

y = y = 1x

Concept Check

A line with slope 4 and y-intercept -1 is:

y = 4x - 1

y = -4x + 1

y = 4 - x

y = x - 1

Concept Check

If b = 5, which point must lie on the line?

(5,0)

(0,5)

(1,5)

(5,1)

Common Misconception

Always verify your result in context instead of trusting a first pass.

Write equation from graph

These steps are out of order — can you fix them?

1.Check with another point

2.Substitute m and b into y=mx+b

3.Compute slope from two points

4.Locate y-intercept

Short Answer

What should you check after writing y = mx + b from a graph?

Mastery Check

Pass this check with at least 80% to unlock completion.

Question 1