[tex]\bf 8^y=16^{y+2}\qquad
\begin{cases}
8=2^3\\
16=2^4
\end{cases}\implies (2^3)^y=(2^4)^{y+2}\implies 2^{3y}=2^{4(y+2)}
\\\\\\
\textit{since the bases are the same, the exponents must also be the same}
\\\\\\
3y=4(y+2)\implies 3y=4y+8\implies -8=y[/tex]
