Answer:
1. y = -3/2 x +11
2. y = -2 x -7
Step-by-step explanation:
Slope intercept form is y = mx+b
1. A (8, –1) and B (–4, 17)
First we need to find the slope
m = (y2-y1)/(x2-x1)
m = (17--1)/(-4-8)
=(17+1)/(-4-8)
=18/-12
Dividing top and bottom by 6
=-3/2
Given the slope
y = -3/2 x+b
Using the point (8,1) we can find b
-1 = -3/2(8) +b
-1 =-12 +b
Add 12 to each side
-1+12 = -12+12 +b
11 =b
The equation is y = -3/2 x +11
2. C (–19, 31) and D (1, –9)
First we need to find the slope
m = (y2-y1)/(x2-x1)
m = (-9-31)/(1--19)
=(-40)/(1+19)
= -40/20
=-2
Given the slope
y = -2 x+b
Using the point (1,-9) we can find b
-9 = -2(1) +b
-9 =-2 +b
Add 2 to each side
-9+2 = -2+2 +b
-7 =b
The equation is y = -2 x -7
