Radius Circumference 2p The formula to find the area when radius is given is. Putting r C and d in terms of A the equations are. C p o.
Substitute this value to the formula for circumference.
Circumference of circle p x Diameter of circle. Write down the circumference formula. This is also known as the longest chord of the circle. It was originally defined as the ratio of a circles circumference to its diameter see second formula below on why and appears in many formulas in mathematics physics and everyday life.