How to "rotate" a polar equation?

Question

Take a simple polar equation like r = θ/2 that graphs out to:

But, how would I achieve a rotation of the light-grey plot in this image (roughly 135 degrees)? Is there a way to easily shift the plot?

Answer 1

Just put $\theta-135^\circ$ in place of $\theta$. Or if you're working in radians, then the equivalent in radians.