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Triangle Inequality Theorem

Sum of the lengths of any two sides of a triangle is greater than the third side.

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Triangle Inequality Theorem
Teacher Contributed

RWA Triangle Inequality Theorem


History of Math


  • Triangle Inequality Theorem

Student Exploration

How long ago was the triangle inequality theorem first written down?

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Read more here: http://www.historyforkids.org/learn/greeks/science/math/euclid.htm

A fragment of Euclid's elements found at Oxyrhynchus, which is dated to circa 100 AD. The diagram accompanies Proposition 5 of Book II of the Elements. http://en.wikipedia.org/wiki/Euclid's_Elements

Extension Investigation

Solve problems using the Triangle Inequality Theorem


Triangle Inequality Theorem


Layering (optional)

Triangle Inequality Theorem



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