Answer:
13x + 11y = 212
Explanation:
total cost of purchasing an item = unit cost x total units purchased
total cost of purchasing pepperoni pizza = 13 × x = 13x
total cost of purchasing plain pizza = 11 × y = 11y
total cost of purchasing both items = total cost of purchasing pepperoni pizza + total cost of purchasing plain pizza
- 13x + 11y = 212