Pre-Calculus homework help??

Question

would this equation graph a circle?

x squared + y squared - 1 = 0

i know I'm supposed move 1 to the other side and then complete the square, but its not possible right?

Answer 1

Yes, this is a circle.  With a radius of 1 and a center of (0,0)

(x-h)² + (y-k)² = R²  <-- formula for a circle

x² + y² - 1 = 0

x² + y²  = 1

h=0, k=0, R = 1