If we are given $x$ such that $25^x-9^y=18$ and $5^x-3^y=3$, compute $5^x+3^y$.
We can factor accordingly: \(25^x - 9^y = (5^x + 3^y)(5^x-3^y)\)
Therefore, \(18 = (5^x+3^y)(3)\)
and the answer is 6.
+230 
+1224 
