Answer:
Explanation:
Given
Points (-1,7) and (1,3)
Formula
m = (y2 = y1) / (x2 - x1)
y2 = 7
y1 = 3
x2 = - 1
x1 = 1
Solution
m = (7 - 3) / (-1 - 1)
m = 4 / - 2
m = - 2
Now use either one of the points to get b in y = mx + b
x = 1
y = 3
m = - 2
y = mx + b
3 = -2 (1) + b
3 = -2 + b
b = 3 + 2
b = 5
Equation: y = - 2x + 5
Second question.
y = -2 + 1
Think money. You have a dollar in your pocket, but you owe your mom 2 dollars. Where are you.
y = -2 + 1
y = - 1