Triangle Inequality Theorem

Front

What is the Triangle Inequality Theorem?

Back

The Triangle Inequality Theorem states that the sum of the lengths of any two sides of a triangle must be greater than the length of the third side.

Front

Do the following side lengths form a triangle? 2 inches, 2 inches, 4 inches

Back

No, because 2 + 2 is not greater than 4.

Front

What is the measure of angle f if f + 122 degrees = 180 degrees?

Back

58 degrees.

Front

Does a triangle with these side lengths exist? 18, 22, 5

Back

Yes, because 18 + 5 > 22, 18 + 22 > 5, and 22 + 5 > 18.

Front

Which of these lengths CANNOT represent the sides of a triangle? 32, 34, 60, 28, 30, 58, 13, 20, 27, 2, 4, 5

Back

28, 30, 58.

Front

Does a triangle with these side lengths exist? 5, 10, 15

Back

No, because 5 + 10 is not greater than 15.

Front

If a triangle has sides of lengths 7, 10, and 12, does it satisfy the Triangle Inequality Theorem?

Back

Yes, because 7 + 10 > 12, 7 + 12 > 10, and 10 + 12 > 7.

Front

What is an example of side lengths that can form a triangle?

Back

3, 4, and 5 can form a triangle because 3 + 4 > 5.

Front

What is an example of side lengths that cannot form a triangle?

Back

1, 2, and 3 cannot form a triangle because 1 + 2 is not greater than 3.

Front

What is the minimum length of the third side if two sides of a triangle are 8 and 6?

Back

The minimum length of the third side must be greater than 2 (8 - 6).