Exploring Triangle Inequality Theorem

Use the sliders to explore the circumstances under which a triangle cannot be constructed. Then answer the questions below the applet.

What are the restrictions on the three side lengths that can form a triangle? For example, if two sides of a triangle are 6 cm and 9 cm long, what is the longest side that could join these two sides to form a triangle? What is the shortest possible length?

Triangle Inequality

Fill in the missing word in the statement below. The sum of two lengths of any two sides of a triangle is _______ than the length of the third side.