Base Length of an Isosceles Triangle Calculator

An online calculator to find the base altitude of a triangle. The altitude of a triangle that is, the line is perpendicular to the base line containing the opposite side is called the extended base of the altitude. Use the below online Base Length of an Isosceles Triangle Calculator to calculate the base of altitude 'b'. Enter the known values of triangle's base length and side length and finally click calculate button to get the resultant value.

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Formula:

Base Length of an Isosceles Triangle = √(4a2-b2) / 2 Where, a = Side Length b = Base Length

Example:

An Isosceles triangle with base length of 12 cm and side length of 15 cm. Find its base length.

Solution

Base Length of an Isosceles Triangle = √(4 x 152 - 122) / 2
= 13.7477 cm

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