Question

Use the work shown below to write the equation for a line that passes through the points (−5, 0) and (−1, −8).

1. Use slope formula to find slope:

2. Substitute one point and slope into slope-intercept form to find the y-intercept:

Answer 1

1) slope: -2

2) y-intercept: -10

Equation:

y = -2x - 10

Explanation:

1) slope: (-8 - 0)/(-1 - -5)

= -8/4 = -2

2) y = -2x + c

0 = -2(-5) + c

c = -10

Equation:

y = -2x - 10

Answer 2

M = -2

b = -10

Explanation:

First we need to find the slope

m = (y2-y1)/(x2-x1)

m = (-8 -0)/(-1- -5)

= (-8-0)/(-1+5)

= -8/4

= -2

We now want to find the y intercept

y = mx+b is the slope intercept form of the equation

y = -2x+b

Using the point (-5,0)

0 = -2(-5) +b

0 = 10+b

Subtract 10 from each side

-10 = 10-10+b

-10 =b

The y intercept is -10

y= -2x-10