Replace the Cartesian equation $(x-5)^2 + y^2 = 25$ by an equivalent polar equation.
Let $t= \theta$, $r=5$, $x=r\cos t$, $y=r\sin t$.
I began with $x=5\cos t-5=5(\cos t-1)$ and $y=5\sin t$. Is that the correct procedure?
Then for $y=mx$, $$5\sin t=m(5\cos t-5)$$ which is $$m=(5\sin t)/(5(\cos t-1))$$ so $$m=(\sin t)/(\cos t-1).$$ Does this mean that the polar equation is $r=(\sin t)/(\cos t-1)$? Or is there more to this problem? Is there some other method I should use to obtain the polar equation?