Video solutions to help Grade 7 students learn how to add and subtract rational
numbers using the number line.

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.

Rotate to landscape screen format on a mobile phone or small tablet to use the **Mathway** widget, a free math problem solver that **answers your questions with step-by-step explanations**.

You can use the free Mathway calculator and problem solver below to practice Algebra or other math topics. Try the given examples, or type in your own problem and check your answer with the step-by-step explanations.

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