What is the polar equation for #x^2+y^2=9#?

1 Answer
Apr 7, 2018

Answer:

#x=3costheta#
#y=3sintheta#

Explanation:

the equation #y^2+x^2=9# is an equation of a circle

it's radius is #3# and it's center is #(0,0)#

and to find the the polar equation of a circle you use the following formula
#x=h+rcostheta#
#y=k+rsintheta#

where #(h,k)# is the center of the circle which is in this case is #(0,0)#
and by substituting You get:
#x=3costheta#
#y=3sintheta#