Any point P with coordinates (\(x,~y\)) on the circumference of a circle can ... This means that, using Pythagoras’ theorem, the equation of a circle with radius \(r\) and centre (0, 0) is ...

D shows the circumference. This is the perimeter of the circle, the distance around the shape. Substitute the value of the radius into the formula. Multiply 2 by π then multiply by the radius, ...

Originally defined as the ratio between the circumference of a circle and its diameter ... written in the form of an equation ...