SOLUTION: You will purchase some CDs and DVDs. If you purchase 6 CDs and 5 DVDs, it will cost you $80.85 ; if you purchase 5 CDs and 6 DVDs, it will cost you $84.15. How much does each C

Algebra ->  Customizable Word Problem Solvers  -> Finance -> SOLUTION: You will purchase some CDs and DVDs. If you purchase 6 CDs and 5 DVDs, it will cost you $80.85 ; if you purchase 5 CDs and 6 DVDs, it will cost you $84.15. How much does each C      Log On

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Question 977489: You will purchase some CDs and DVDs. If you purchase 6 CDs and 5 DVDs, it will cost you $80.85 ; if you purchase 5 CDs and 6 DVDs, it will cost you $84.15. How much does each CD cost and how much does each DVD cost?
Answer by Cromlix(4381) About Me  (Show Source):
You can put this solution on YOUR website!
Hi there,
Make CDs = x
and DVDs = y.
Form two equations:-
6x + 5y = 80.85......(1)
5x + 6y = 84.15......(2)
Multiply (1) by 6
Multiply (2) by 5
36x + 30y = 485.1.....(1)
25x + 30y = 420.75....(2)
Subtract (2) from (1)
11x = 64.35
x = 5.85
Substitute x = 5.85
into (2)
5x + 6y = 84.15
5(5.85) + 6y = 84.15
29.25 + 6y = 84.15
........6y = 84.15 - 29.25
........6y = 54.90
.........y = 9.15
CD costs $5.85
DVD costs $9.15
Hope this helps:-)