You are buying decorations for a birthday party. Six rolls of crepe paper and 20 balloons cost $11.90. After you start decorating, you need more supplies. You buy 2 more rolls of crepe paper and 15 more balloons for $6.05. How much did each roll of crepe paper cost?
A)
$1.15
B)
$ 1.58
C)
25¢
D)
22.6¢

Question

hero · Answer

Hint: 

6c + 20b = 11.90
2c + 15b = 6.05

anonymous · Answer

What am I supposed to do with the two equations?

hero · Answer

Apply systems of equations

anonymous · Answer

What is that?

hero · Answer

6c + 20b = 11.90
2c + 15b = 6.05

c = (11.90 - 20b)/6
c = (6.05 - 15b)/2

c = c

2(11.90 - 20b = 6(6.05 - 15b)
23.80 - 40b = 36.30 - 90b
90b - 40b = 36.30 - 23.80
50b = 12.50
b = 12.50/50

b = .25
c = 1.15

So the crept paper cost $1.15

anonymous · Answer

Thank you is what you just did a system of equations?