Objective• Write equations in slope-intercept form.• Identify slope and y-intercept from an equation.

3.2Slope-Intercept

Form of a Linear Equation

Slope–Intercept Form

of a Linear Equation

y = mx + bm represents the slope

b represents the y-intercept

Writing Equations

When asked to write an equation for a line in slope-intercept form, you need to know two things:

1) slope (m)

2) y-intercept (b).

Writing Equations Write an equation in slope-intercept form of the line that has a slope of 2 and a y-intercept of 6.

To write an equation, you need two things:

slope (m) =

y – intercept (b) =

We have both!! Plug them into slope-intercept form

y = mx + b

y = 2x + 6

2

6

Write the equation of a line that has a y-intercept of -3 and a slope of -4.A. y = -3x – 4

B. y = -4x – 3

C. y = -3x + 4

D. y = -4x + 3

To find the slope and y-intercept of an equation, write the equation in slope-intercept form: y = mx + b.

Find the slope and y-intercept.

1) y = 3x – 7

y = mx + b

m = 3, b = -7

Find the slope and y-intercept.

2) y = x

y = mx + b

y = x + 0

3) y = 5

y = mx + b

y = 0x + 5

2

3m =

b = 0

2

3

2

3

m = 0b = 5

-3 -3 -3

Find the slope and y-intercept.4) 5x – 3y = 6

Write it in slope-intercept form. (y = mx + b)

5x – 3y = 6

-3y = -5x + 6

y = x – 25

3m =

b = -2

5

3

Write it in slope-intercept form. (y = mx + b)

2y + 2 = 4x

2y = 4x – 2

y = 2x – 1

Find the slope and y-intercept. 5) 2y + 2 = 4x

2 2 2

m = 2b = -1

Find the slope and y-intercept of y = -2x + 4

1. m = 2; b = 4

2. m = 4; b = 2

3. m = -2; b = 4

4. m = 4; b = -2

Assignment

3.2 Worksheet