Question

nothing

Answer 1

The two points should be (1,-3) and (3,1)

Answer 2

I m sorry I thought it was f(3)-f(1) / (3-1)
f(3) = 3^2+3 =12
f(1)=1^2+1=2

Answer 3

The slope is positive because the line going through (1,-3) and (3,1) goes up (as you move from left to right)

Answer 4

how did you get f(x) = x^2 + x ?

Answer 5

yes it's 2