The graph of a function is a line that passes through the points (1,4) , (3,8) , and (6,y) . What is the value of y ?

Answer 1

First, find the slope from the first 2 points, then use the value of the slope and either one of the first 2 points to find y in the 3rd point.

m = (8 - 4)/(3 - 1) = 4/2 = 2

2 = (y - 4)/(6 - 1)

Now solve for y. You should be able to finish from here.