Question

How to get the radius of a circle

Answer 1

simply get the diameter and divide it by 2 to get the half of the diameter which is the radius.

Answer 2

Radius of the circle can be obtained through different formulas. I will show you how to get it from Circumference and Area of the circle. We know that radius r equals to diameter divided by 2.

First we must be familiar with those two formulas.

We know that Area of circle is
`A=\pi r^2` where r is our radius. We can solve the equation for r using operations on both sides of the equation hence,

`A=\pi r^2\\A/\pi =(\pi r^2)/\pi \\r^2=A/\pi\\\boxed{r=√(A/\pi)}`

We also know that Circumference C of circle is
`C=2\pi r` where again r is our radius. And again solve for r.

`C=2\pi r\\C/2\pi = 2\pi r/2\pi\\\boxed{r=C/2\pi}\\`

Hope this helps.

r3t40