General Form of a Circle:
r^2 = (x - a)^2 + (y - b)^2
Is it true that the coefficients for x, y, (x - a), and (y - b) terms should always be equal to each other or 1?
For example, could these be considered equations of a circle?
2x^2 + y^2 = 9
(2x - 3)^2 + y^2 = 9