How do you convert #Y=4x^2# into polar form? Precalculus Polar Coordinates Converting Equations from Polar to Rectangular 1 Answer Bdub Sep 12, 2017 see below Explanation: Use the formula #x = r cos theta, y = r sin theta# Hence, #y=4x^2# #r sin theta = 4r^2 cos^2 theta# #:. 0=4r^2 cos^2 theta -r sin theta# Answer link Related questions What is the polar equation of a horizontal line? What is the polar equation for #x^2+y^2=9#? How do I graph a polar equation? How do I find the polar equation for #y = 5#? What is a polar equation? How do I find the polar equation for #x^2+y^2=7y#? How do I convert the polar equation #r=10# to its Cartesian equivalent? How do I convert the polar equation #r=10 sin theta# to its Cartesian equivalent? How do you convert polar equations to rectangular equations? How do you convert #r=6cosθ# into a cartesian equation? See all questions in Converting Equations from Polar to Rectangular Impact of this question 15150 views around the world You can reuse this answer Creative Commons License