Answer
$x=7$ and $y=4$
Work Step by Step
Given the two equations,we need to find the value of $x$ and $y$.
Hence, $\frac{a^{x}}{a^{y}}=$ $a^{x-y}=$ $a^{3}$ and $\frac{a^{x}}{a^{3y}}=$ $a^{x-3y}=$ $a^{-5}$
(since $\frac{a^{m}}{a^{n}}=a^{m-n}$)
Thus, Hence $x-$$y=$ $3$ and $x-$ $3y=$ $-5$
After subtracting the second equation from first, we get :
$2y=$ $8$
Hence, $y=$ $4$
Substituting the value of $y$ in the first equation , we get :
$x=$ $y+3=$ $4+3=$ $7$