Lesson 10

Equation of a line

y = m x + b

(-3,2)

(4,-3)

Graph point (-3,2)

Graph point 4,-3)

Draw line

Draw vertical side of triangle

Draw horizontal side of triangle

(-3,2)

(4,-3)

y is changing from 2 to -3

Change in y = (-3) – (2)

Change in y = -5

Y = 2

Y = 1

Y = 0

Y = -1

Y = -2

Y = -3

(-3,2)

(4,-3)

x is changing from -3 to 4

Change in x = (4) – (-3)

Change in x = 7

x = -3

x = -2

x = -1

x = 0

x = 1

x = 2

x = 3

x = 4

(-3,2)

(4,-3)

Change in y = -5

Change in x = 7

7

5

7

5

xinchange

yinchangem

7

5mslope

(-3,2)

(4,-3)

Change in y = -5

Change in x = 7

? 7

5 bm

bmxy Slope-intercept form of a line.

(-3,2)

(4,-3)

Change in y = -5

Change in x = 7

? 7

5 bm

bmxy Slope-intercept form of a line.

b is the y-intercept

It appears to be 0. Is it?

bxy 7

5

b )3(7

52

b7

152 b

7

1

7

1

7

5

xy

bmxy