Circles
Non-Standard Form
If the equation is not given in standard form, it will need to be converted to standard form by completing the square. To identify an equation as a circle, it will contain an x2 and y2 term with equal coefficients. See the following examples:
- -3x2 - 3y2 + x - y = 5 is a circle.
- 3x2 - 3y2 + x - y = 5 is not a circle.
- 3x2 + 3y = 5 is not a circle.