AJ L. answered 04/19/23
Patient and knowledgeable Precalculus Tutor
x2+(y-5)2=25
(r·cosθ)2 + (r·sinθ - 5)2 = 25 <-- Recall x=r·cosθ and y=r·sinθ
r2cos2θ + r2sin2θ - 10rsinθ + 25 = 25
r2(cos2θ + sin2θ) - 10r·sinθ = 0
r2 - 10r·sinθ = 0 <-- Pythagorean Identity
r2 = 10r·sinθ
r = 10sinθ
Hope this helped!