SOLUTION: Having trouble solving this work problem. Melissa bought a desktop computer and a laptop computer. Before finance charges, the laptop cost $400 less than the desktop. She paid for

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Question 852773: Having trouble solving this work problem.
Melissa bought a desktop computer and a laptop computer. Before finance charges, the laptop cost $400 less than the desktop. She paid for the computers using two different financing plans. For the desktop the interest rate was 8.5% per year, and for the laptop it was 5% per year. The total finance charges for one year were $412 . How much did each computer cost before finance charges?

Found 2 solutions by josgarithmetic, josmiceli:
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
d for price of desktop
n for price of laptop (notebook)

n=d-400

interest rate for d was 8.5%
interest rate for d-400 was 5%
total 1 year finance charges were 412.

d%2A0.085%2B%28d-400%29%280.05%29=412, and remember, n=d-400.

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
This is the way I read it:
Let +c+ = the cost of the desktop
+c+-+400+ = the cost of the laptop
--------------------------------
+.085c+%2B+.05%2A%28+c+-+400+%29+=+412+
+.085c+%2B+.05c+-+20+=+412+
+.135c+=+432+
+c+=+3200+
+c+-+400+=+2800+
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The cost of the desktop before finance charges is $3,200
The cost of the laptop before finance charges is $2,800