Question

What is an equation for the line that passes through points (–1, –4) and (1, 4)? Write the equation in slope-intercept form.

Answer 1

Insert each point into y = xm + b:

-4 = -1m + b
4 = 1m + b

Isolate b in each equation:

b = m - 4
b = 4 - m

set b = b
m - 4 = 4 - m
m + m = 4 + 4
2m = 8
m = 8/2
m = 4

b = m - 4
b = 4 - 4
b = 0

y = 4x

Answer 2

thanks ! i judt didnt understand what to do haha