Y=6.75x
He charges $6.75 per hour
This document has the answer
Slope of a Line Passing through two points (x₁ , y₁) and (x₂ , y₂) is given by :

Given Points are (1 , 7) and (-4 , -8)
here x₁ = 1 and x₂ = -4 and y₁ = 7 and y₂ = -8

3 is answer
Answer:














hope this helps
sorry, I don't know how solve the 12th one.
thanks.