Answer
The graph is a circle whose center is at $(-2,0)$ with radius $2$.
Work Step by Step
Conversion of polar coordinates and Cartesian coordinates are as follows:
a)$r^2=x^2+y^2 \implies r=\sqrt {x^2+y^2}$
b) $\tan \theta =\dfrac{y}{x} \implies \theta =\tan^{-1} (\dfrac{y}{x})$
c) $x=r \cos \theta$
d) $y=r \sin \theta$
Here, we have $r^2\cos^2 \theta +r^2 \sin^2 \theta=-4 r \cos \theta$
Therefore, our Cartesian equation is $x^2+y^2=-4x \implies (x+2)^2+y^2=4$
This shows that the graph is a circle whose center is at $(-2,0)$ with radius $2$.
