Given:
The given polar equation is:
[tex]r=8\cos\theta[/tex]
To find:
The rectangular form of the given polar equation.
Solution:
We know that,
[tex]r^2=x^2+y^2[/tex]
[tex]x=r\cos \theta[/tex]
We have,
[tex]r=8\cos\theta[/tex]
Multiply both sides by r.
[tex]r^2=8r\cos\theta[/tex]
[tex]x^2+y^2=8x[/tex]
Therefore, the correct option is D.