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

Can the side lengths 3, 5, and 8 form a triangle?

Back

No, because 3 + 5 is not greater than 8.

Front

What is the total measure of angles in a triangle?

Back

180 degrees.

Front

If two angles of a triangle are 50° and 80°, what is the measure of the third angle?

Back

50°, because 180° - (50° + 80°) = 50°.

Front

How many unique triangles can be formed with angles 80°, 50°, and 50°?

Back

More than one unique triangle exists with the given angle measures.

Front

Which of the following sets of side lengths can form a triangle: 3, 6, 12 or 7, 7, 14?

Back

Neither can form a triangle because 3 + 6 is not greater than 12 and 7 + 7 is not greater than 14.

Front

What is the relationship between the sides of a triangle and its angles?

Back

The larger the angle, the longer the opposite side.

Front

If a triangle has sides of lengths 5, 12, and 13, does it satisfy the Triangle Inequality Theorem?

Back

Yes, because 5 + 12 > 13, 5 + 13 > 12, and 12 + 13 > 5.

Front

What is an isosceles triangle?

Back

An isosceles triangle has at least two sides of equal length.

Front

What is a scalene triangle?

Back

A scalene triangle has all sides of different lengths.