Question

Two friends went to a restaurant and ordered one plain pizza and two sodas . Their bill totaled $15.95. Later that day, five friends went to the sane restaurant. They ordered three plain pizzas and each person had one soda. Their bill totaled $45.90. Write and solve a system of equations to determine the price of one plain pizza.

Answer 1

Assume the price of one pizza is x and the price of one soda is y.
1) x+2y=15.95
2) 3x+5y=45.90
multiply equation (1) by -3 and add the result to equation (2).
y=$1.95 (one soda)
Replace y in the first equation: x=$12.05