Question

Someone help me please

Answer 1

(a) The gradient is
`(40)/(5)=\boxed{8}`, and represents the cost of buying one book in dollars.

(b) Draw the line through (0,0) and (20, 130).

(c) Since the gradient of the line representing company B is less (6.5 vs 8), it is better to buy books from company B because they are cheaper.