Question

Elle ordered some large pizzas and some medium pizzas for a party. In all, she ordered 18 pizzas. Large pizzas cost $14, and medium pizzas cost $10. In all, she spent $204. Determine if each equation is a part of the system of equations that can be used to find the number of each type of pizza that was ordered. The variable x represents the number of large pizzas, and y represents the number of medium pizzas.

Answer 1

l+m=18, l=18-m

14l+10m=204 using l found above in this we get:

14(18-m)+10m=204

252-14m+10m=204

252-4m=204

-4m=-48

m=12, since l=18-m

l=6

So Elle ordered 6 large and 12 medium pizzas.