Triangle Sum Theorem

Front

What does the Triangle Sum Theorem state?

Back

The Triangle Sum Theorem states that the sum of the interior angles of a triangle is always 180°.

Front

If one angle of a triangle is 50° and another is 60°, what is the measure of the third angle?

Back

The third angle is 70° because 180° - (50° + 60°) = 70°.

Front

What is the measure of each angle in an equilateral triangle?

Back

Each angle in an equilateral triangle measures 60°.

Front

How do you find the measure of an unknown angle in a triangle?

Back

To find an unknown angle, subtract the sum of the known angles from 180°.

Front

What is the sum of the angles in a triangle?

Back

The sum of the angles in a triangle is 180°.

Front

If a triangle has angles measuring 30° and 90°, what is the measure of the third angle?

Back

The third angle measures 60° because 180° - (30° + 90°) = 60°.

Front

What is the relationship between the angles in a right triangle?

Back

In a right triangle, one angle is 90°, and the sum of the other two angles is 90°.

Front

What type of triangle has all angles less than 90°?

Back

A triangle with all angles less than 90° is called an acute triangle.

Front

What type of triangle has one angle greater than 90°?

Back

A triangle with one angle greater than 90° is called an obtuse triangle.

Front

If two angles of a triangle are 45° and 45°, what is the type of triangle?

Back

The triangle is an isosceles triangle because it has two equal angles.