Answer
The rectangular equation is, $x=6$
Work Step by Step
Using, $r\cos \theta =x$ we will convert the polar equation to the rectangular equation.
Therefore,
$\begin{align}
& r=6\sec \theta \\
& r=\frac{6}{\cos \theta } \\
& r\cos \theta =6 \\
& x=6
\end{align}$
