In this tutorial you are shown how the equation of a circle is derived when you know the centre and radius.
Formulae to remember:
- (x – x1)2 + (y – y1)2 = r2 where the centre has coordinates (x1 , y1) and radius = r2
You will also be taken through this example.
Example:
- Find the equation of a circle with centre (4, -2) and radius 3.