Triangle Inequality Theorem

Explore the Triangle Inequality Theorem

The triangle inequality theorem states that

The sum of any two sides of a triangle must be greater than the length of the third side.

Move the a, b and c slider bars to change the lengths of sides of the triangle.

Look at the three conditions
b + c > a
a + c > b
a + b > c

See what happens to the triangle when one of the above conditions is not true.

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