polar form is (r,θ) where r is the radius and tan θ = x/y
The equation you provided is a circle so 9 = r² → r = 3
tan θ = 1/1
tan θ = 1
[tex] tan^{-1} [/tex] (tan θ) = [tex] tan^{-1} [/tex] (1)
θ = 45°
Answer: (3, 45°) or (3, [tex] \frac{ \pi}{4} [/tex])
