How do you change the rectangular equation #x^2+y^2=4# into polar form? Trigonometry The Polar System Converting Between Systems 1 Answer Douglas K. Oct 2, 2016 Substitute #r²# for #x² + y²# and then take the square root #r² = 4# #r = 2# Explanation: Please see above. Answer link Related questions How do you convert rectangular coordinates to polar coordinates? When is it easier to use the polar form of an equation or a rectangular form of an equation? How do you write #r = 4 \cos \theta # into rectangular form? What is the rectangular form of #r = 3 \csc \theta #? What is the polar form of # x^2 + y^2 = 2x#? How do you convert #r \sin^2 \theta =3 \cos \theta# into rectangular form? How do you convert from 300 degrees to radians? How do you convert the polar equation #10 sin(θ)# to the rectangular form? How do you convert the rectangular equation to polar form x=4? How do you find the cartesian graph of #r cos(θ) = 9#? See all questions in Converting Between Systems Impact of this question 927 views around the world You can reuse this answer Creative Commons License