Question 1200646
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<pre>

x dollars for the desktop;  (x+450) dollars for the laptop.


Write one year total finance charges equation 

    0.09*x + 0.06*(x+450) = 300  dollars.


Simplify and find x.


etc.
</pre>

The rest is simple arithmetic.


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To see many other similar solved problems using one equation in one unknown, &nbsp;look into the lesson

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/equations/Typical-investment-problems.lesson>Typical investment problems</A>

in this site.


To see many other similar solved problems using systems of two equations in two unknowns, &nbsp;look into the lesson

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/coordinate/lessons/Using-systems-of-equations-to-solve-problems-on-investment.lesson>Using systems of equations to solve problems on investment</A>

in this site.