If the graph of the line y = ax + b passes through the points (4,5) and (8,11)$, what is a - b?

Guest Jul 15, 2020

#1**+1 **

a is the slope and b the y intercept. We solve for the slope first. Plugging the points into the slope formula, we find that a is 6/4=3/2. So now we have y=3/2x+b. Then we plug in either of the given points to solve for b.

y=3/2x+b

5=3/2(4)+b

5=6+b

b=-1

Therefore the equation of the line is **y=3/2x-1.**

gwenspooner85 Jul 15, 2020