Brandy and Jennifer are selling wrapping paper for a school fundraiser.

Question

Customers can buy rolls of plain wrapping paper and rolls of holiday wrapping paper. Brandy sold 2 rolls of plain wrapping paper and 1 roll of holiday wrapping paper for a total of​ $43. Jennifer sold 7 rolls of plain wrapping paper and 1 roll of holiday wrapping paper for a total of​ $93. Write a system of Linear Equations and find how much each type of wrapping paper costs per roll algebraically​ (Not graphing).
​Understand​ & Think​: Do you understand what is being asked and what you need​ to​ do? Do you have a list of things​ you​ know, ideas​ to​ try, and a plan for​ doing​ it? Identify the problem and list your strategies.

Answer 1

Problem: Find how much each type of wrapping paper costs per roll algebraically.
Strategies:
1. Write a system of linear equations
2. Solve the system of equations

System of Linear Equations:
Let x = cost of plain wrapping paper per roll
Let y = cost of holiday wrapping paper per roll

2x + y = 43
7x + y = 93

Solve the system of equations:
7x + y = 93
-2x - y = -43

5x = 50
x = 10

Substitute x = 10 into 2x + y = 43
2(10) + y = 43
20 + y = 43
y = 23

Answer:
The cost of plain wrapping paper per roll is $10 and the cost of holiday wrapping paper per roll is $23.