Math Question College Algebra

Question

On Tuesday Zan ordered two pizzas and shelled out $16 for them. On Friday, xe ordered 8 pizzas and paid $55. Find a linear function which models the cost C of pizza delivery for Zan as a function of the number of pizzas p.

Answer 1

(55 - 16)/(8 - 2) = 39/6 = 6.5

So, each pizza costs $6.50, but there is apparently a base charge, because 6.5(8) ≠ 55.

To find our y-intercept (technically the cost to order 0 pizzas), we use either "point."

55 = 6.5(8) + b

55 = 52 + b

b = 3

f(p) = 6.5p + 3

This means that it's $6.50 per pizza us a flat $3.