A restaurant offers delivery for their pizzas. The total cost is a delivery fee added to the price of the pizzas. One customer pays $25 to have two pizzas delivered. Another customer pays $58 for five pizzas. How many pizzas are delivered to a customer who pays $80?

7

Step-by-step explanation:

We know, slope = rise / run. We can use this slope formula to find out the value of every pizza.

So, 58-25 / (5-2) = 33 / 3 = 11

So, every pizza costs $11

Now, A customer pays $80 for a number of pizzas. So, if we divide 80 by 11 we can find the value of unknown number of pizzas he ordered.

So, 80/11 = 7.27

Here, pizzas can't be fraction and cost of a delivery fee is added to the cost. So, we can remove the fraction.

So, the customer ordered 7 pizzas for $80.