



 
Hi Susan, I would begin by simplifying the first equation \[(28x + 36y)  [20000  .75(28x + 36y) + 60000] = (28x + 36y)  20000 + \frac34 (28x + 36y)  60000 \] and hence the first equation can be written \[\frac74 (28x + 36y) = 49x + 63y = 85000.\] Solve the second equation, $x + y = 10000$ for $y$ and substitute into the simplified form of the first equation and solve for $x.$ Penny
 


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