Why won't Desmos plot my polar circle equation r² - 8r cos(θ) = -12?

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karush
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The given is
determine a polar equation for circle satisfying the given conditions: the radius is $2$, and the polar coordinates for the center are: $\left(4,0\right)$
I got ${r}^{2}-8r\cos\left({\theta}\right)=-12$
But when I try to plot this to DESMOS get nutin.
 
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I would begin with the Cartesian equation of that circle:

$$(x-4)^2+y^2=2^2$$

$$x^2-8x+16+y^2=4$$

$$x^2+y^2=8x-12$$

Convert to polar:

$$r^2=8r\cos(\theta)-12$$

Try W|A for polar plots:

W|A - r^2=8rcos(theta)-12
 
Apparently r has to be isolated for Desmos