Greg bought a desktop computer and a laptop computer.
Before finance charges, the laptop cost $300 more than the desktop.
Let Desktop cost be x
Then Laptop cost be x + 300
He paid for the computers using two different financing plans.
For the desktop the interest rate was 9% per year, and for the laptop it was 7% per year.
Interest on desktop = 0.09x
Interest on laptop = 0.07 (x+300)
The total finance charges for one year were $365:
[tex]\begin{gathered} \text{Interest}+\text{Interest = }Interest \\ 0.09x+0.07(x+300)=365 \\ 0.09x+0.07x+21=365 \\ \text{collect like terms} \\ 0.16x=365-21 \\ 0.16x=344 \\ x=2150 \end{gathered}[/tex]Therefore the cost of the desktop = $2150
and the cost of the laptop = $2150+300 = $2450
