Answer
$(6, \pi)$
Work Step by Step
To change from rectangular to polar coordinates, use
$r^{2}=x^{2}+y^{2}$ and $\displaystyle \tan\theta=\frac{y}{x}$.
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$r^{2}=(-6)^{2}+0^2=36$
$r=\pm 6$
$\displaystyle \tan^{-1}(\frac{0}{-6})=\tan^{-1}(0)=0$
has the positive x-axis as its terminal side.
The point P$(-6,0)$ lies on the negative x-axis,
so we take $\theta=0+\pi=\pi$.
The terminal end of $\theta$ passes through P, so for this angle, r is positive.
Polar coordinates: $(6, \pi)$
