Convert the Cartesian equation x^2 - y^2 = 16 to a polar equation.

Question

r² = 16/cos2è
r = -4
r² = 8

help please im stuck between 2 answers.

Answer 1

x = rcosθ
y = rsinθ

x^2 - y^2 = r^2 cos^2 θ - r^2 sin^2 θ
= r^2(cos^2 θ - sin^2 θ) = r^2 cos2θ

so, we have r^2 cos2θ = 16
r^2 = 16/cos2θ

Answer 2

Thank you.