## What is the formula for radius?

The two formulas that are useful for finding the radius of a circle are C=2*pi*r and A=pi*r^2.

We use algebra skills in solving for our variable r.

We know that the constant pi is always 3.14.

Another word related to the radius is diameter, which is always twice the radius.

## How do you find the radius with the circumference?

How to Find the Radius of a Circle When Given the Circumference

## How do you find the radius when given the area?

Ex: Find the Radius of a Circle Given the Area –

## What is a radius of a circle?

In classical geometry, a radius of a circle or sphere is any of the line segments from its center to its perimeter, and in more modern usage, it is also their length. The name comes from the Latin radius, meaning ray but also the spoke of a chariot wheel.

## What is a radius of a cylinder?

The radius R, or the distance from the center of a cylinder to its edge, and its length, L are usually the defining property of a cylinder. If your cylinder is standing upright, you might call the “length” a “height” instead.

## Is the radius half the circumference?

The circumference is the distance around the circle. In other words, the circle’s perimeter. The diameter is a straight line that passes through the center of the circle. The radius is half of the diameter.

## How do you solve for radius and diameter?

Just remember to divide the diameter by two to get the radius. If you were asked to find the radius instead of the diameter, you would simply divide 7 feet by 2 because the radius is one-half the measure of the diameter. The radius of the circle is 3.5 feet. You can also use the circumference and radius equation.

## What is the radius of a 10cm circle?

Look at the table

Radius | Diameter | Circumference |
---|---|---|

1cm | 2 cm | 6.24cm |

10cm | 20cm | 62.4cm |

20cm | 40cm | 124.8cm |

## What is the radius of 30?

The reason being is that radii ( 2⋅radius ) are equal to the diameter of a circle. Therefore, if the diameter is equal to 30m, then the two radii equals 30m. However, you want the radius, so half of 30m ( 302 ) is 15m.

## How fo you find the area of a triangle?

Example finding area of triangle –

## How do you find area?

To find the area of a rectangle multiply its height by its width. For a square you only need to find the length of one of the sides (as each side is the same length) and then multiply this by itself to find the area. This is the same as saying length2 or length squared.