SOLUTION: a line is written in the form y=mx+b. if the points (4,2) and (-8,5) are on the line, find the value of b-4m

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: a line is written in the form y=mx+b. if the points (4,2) and (-8,5) are on the line, find the value of b-4m      Log On


   

Question 875052: a line is written in the form y=mx+b. if the points (4,2) and (-8,5) are on the line, find the value of b-4m
Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!
We want to find y0 such that (-4,y0) is on the line. Note that -4 is 1/3 of the way from -8 to 4, and 4 is 1/3 of the way from 5 to 2, so (-4,4) is on the line.

Note that if x = -4, y = 4. So 4 = m(-4) + b --> b - 4m = 4.