Question

Find the equation of the line containing the points (-9, -2) and (3,4)

Answer 1

y = mx + b
-2 = -9m + b
4 = 3m + b

9m - 2 = b
4 - 3m = b

b = b
9m - 2 = 4 - 3m
9m + 3m = 4 + 2
12m = 6
m = 6/12
m = 1/2

b = 9(1/2) - 2
b = 4 1/2 - 2
b = 2 1/2
b = 5/2

y = (1/2)x + 5/2
y = (x + 5)/2