find y=mx+b for line parallel to AB.
The line that is parallel will have the same slope as line AB:
the slope of line AB is
m=(8-3)/(-10-2)
=5/-12
=-5/12
Since the line going through X is parallel the vertical distance of the new line to AB is the same for all values of the domain(x-axis).
at x=-5 the point X has the y value of 10 which is 4 more than the y value for AB based on the graph.
To find the intercept b of the line going through X that is parallel to AB we just add 4 to the intercept of AB, which is 4 so
4+4=8
