# Perimeter Of Isosceles Triangle, Isosceles Triangle Perimeter Calculator

## How To Find The Perimeter Of Isosceles Triangle?

Let's look at the geometric characteristics of a isosceles triangle. But first please review the definition of Perimeter Of Two-Dimensional Shapes, Angle and Right Angle.
• An isosceles triangle has two unique features.
• The first unique feature of an isosceles triangle is two sides have exactly the same length: sides A.
• The second unique feature of an isosceles triangle the angles at the base of the triangle are exactly the same. In other words ∠BA and ∠AB are equal. The sum of the interior angles is 180°.
• Special note, all sides of an isosceles triangle must be greater than zero.

Perimeter Of Isosceles Triangle
Perimeter = Side A + Side A + Side B =
Perimeter = 2 A + B =
Perimeter = (2 × A) + B

ALTERNATIVE FORMULA TO COMPUTE PERIMETER:
Perimeter = Side A + Side B + Side C =
Perimeter = A + B + C

Calculate Perimeter Of Isosceles Triangle
Field Name User Input
Length Of A
You can enter up to 6 digits
Length Of B
You can enter up to 6 digits