# Math Help - Cartesian to Polar

1. ## Cartesian to Polar

x^2 + y^2 = 9

Can I just say that r^2 = 9, r = 3. Is this the polar equation? Seems a bit easy.

Cheers.

2. Originally Posted by Sprintz
x^2 + y^2 = 9

Can I just say that r^2 = 9, r = 3. Is this the polar equation? Seems a bit easy.

Cheers.
Yes, it's that easy.

x + y = 9.

Should I state (t = theta):

rcost + rsint = 9
r = 9/(cost + sint)

Or is there a better way to express this? Thanks.

4. Originally Posted by Sprintz