Question

The Anderson family paid $53 to have four pizzas delivered. Five pizzas would cost $65 and 6 pizzas would cost $77. Write an equation to represent the total cost, y, of x pizzas delivered.

Answer 1

The equation is:

`y =12x+5`

Explanation:

Given

`(x,y) = (Pizza,Cost)`

So, we have:

`(x_1,y_1) = (4,53)`

`(x_2,y_2) = (5,65)`

`(x_3,y_3) = (6,77)`

Required

Equation to represent the scenario

First, calculate the slope

`m = (y_2 - y_1)/(x_2 - x_1)`

So, we have:

`m = (65 - 53)/(5 - 4)`

`m = (12)/(1)`

`m=12`

So, the equation is:

`y =m(x - x_1) + y_1`

This gives:

`y =12(x - 4) + 53`

`y =12x - 48 + 53`

`y =12x+5`