Answer
The rectangular equation is, ${{x}^{2}}+{{y}^{2}}=64$
Work Step by Step
Using, ${{r}^{2}}={{x}^{2}}+{{y}^{2}}$, we will convert the polar equation to a rectangular equation.
Therefore,
$\begin{align}
& {{x}^{2}}+{{y}^{2}}={{8}^{2}} \\
& {{x}^{2}}+{{y}^{2}}=64 \\
\end{align}$
