# Pentagon Calculator

A regular pentagon is a polygon with 5 vertices. This form is often used in construction and architecture. Enter one of the known values, then click calculate.

.Pentagon Calculator

**Side length (a)**

**Diagonal (D)**

**Height (h)**

**Периметр(p)**

**Square (S)**

**The radius of the circumscribed circle (R)**

**Radius of the inscribed circle (r)**

**Formulas:**

d = a / 2 * ( 1 + √5 )

h = a / 2 * √ 5 + 2 * √5

Р = 5 * а

S = a2 / 4 * √ 25 + 10 * √5

R = a / 10 * √ 50 + 10 * √5

r = a / 10 * √ 25 + 10 * √5

Angle: 72°, 5 sides.