We want: .A large pizza franchise delivers large pizzas for $16. The equation: .
describes the profit, , based on the increase, , in the price of their large pizzas.
Determine the range of prices, to the nearest cent, for which the franchise
could sell each pizza and still make a profit of at least $640.
We want to know when: . .is above the x-axis.
Since the graph is a down-opening parabola, the curve is above the x-axis
. . between its x-intercepts.
For the x-intercepts, we have: .
Quadratic Formula: .
So we have: .
The franchise can raise the price per pizza by $2.48 or by $21.52
. . or anything in between, and still make at least $640.
The price can range from per pizza.