What is an isosceles triangle?

A triangle with two sides equal. If base and height are known, area = (1/2)×base×height.

How is area computed from sides?

With two equal sides (a) and base (b): height = √(a² - (b/2)²), then area = (1/2)×b×height.

Two equal sides and base (or base and height): find area and perimeter of an isosceles triangle.

Equal side length

Base

What is an isosceles triangle?: A triangle with two sides equal. If base and height are known, area = (1/2)×base×height.
How is area computed from sides?: With two equal sides (a) and base (b): height = √(a² - (b/2)²), then area = (1/2)×b×height.

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