# What Are the Side Lengths of an Isosceles Triangle?

** An isosceles triangle has two side lengths that are equal and a remaining side that is of a different length.** The two interior angles that are opposite these sides are equal to each other. The unequal side length of an isosceles triangle is called the base.

When the unequal angle of an isosceles triangle is 90 degrees, it is referred to as a right isosceles triangle. Each equal angle in a right isosceles triangle is equal to 45 degrees.

In an isosceles triangle, the perpendicular distance from the top vertex point to its base is called the altitude. There are different formulas for finding the legs, altitude and base. For example, the formula for finding the equal legs of this triangle is given as L = square root [A^2 + (B/2)^2], where L represents leg, A is altitude, and B stands for the base.