Area and Perimeter > Pentagon

# Area and Perimeter: Pentagon

This online calculator is a free online tool to help you in calculate area and perimeter of Pentagon.

## Formula

- P – perimeter
- A – area
- R – radius K
- r – radius k

- O – centre
- a – edges
- K – circumscribed circle
- k – inscribed circle

You may need: Pythagorean Theorem

## Pentagon

Pentagon is a five-sided polygon that has five straight sides and five interior angles that sum up to 540^{o}. Pentagon is two-dimensional 5-sided geometric shape. The five sides of pentagon do not intersect and meet each other to form a shape. As a regular pentagon must have five congruent sides and five congruent interior angles.

## The standard formula to count the Area of Pentagon

A=1/4.√(25+10√5)a^{2}

a= side length/edges

## The standard formula to count the Perimeter of Pentagon

P= 5.a

P = perimeter

a = side length/edges

## The Instruction to use the Calculator Online to calculate the Area and Perimeter of Pentagon

1. First, input 1 values between (a) edges of pentagon, (R) Radius K, or (r) Radius k.

2. Next, you can choose what decimal places you need. It can 1 or 2 or whatever you want.

3. And then, click “Calculate Button” and the answer will automatically appear.

4. To count another number, just repeat the first step.

## Example of the usage of calculator online to count the Area and Perimeter of Pentagon

1. Example, enter “5” in “a”/edges.

2. Then click enter or “Calculate” button.

3. You will find the answer right there on the Area A column and Perimeter P column. The area is **43.01** and the Perimeter is **25.00**.