Triangle Sum Theorem and Exterior Angle Theorem

Front

What is the Triangle Sum Theorem?

Back

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

Front

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

Back

In an equilateral triangle, each angle measures 60 degrees.

Front

What is an exterior angle of a triangle?

Back

An exterior angle of a triangle is formed by one side of the triangle and the extension of an adjacent side.

Front

What is the relationship between an exterior angle and the two remote interior angles?

Back

The exterior angle is equal to the sum of the two remote interior angles.

Front

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

Back

The third angle is 70 degrees (180 - 50 - 60 = 70).

Front

What are acute angles?

Back

Acute angles are angles that measure less than 90 degrees.

Front

What are right angles?

Back

Right angles are angles that measure exactly 90 degrees.

Front

What are obtuse angles?

Back

Obtuse angles are angles that measure more than 90 degrees but less than 180 degrees.

Front

If a triangle has angles measuring 30 degrees and 100 degrees, what is the measure of the third angle?

Back

The third angle measures 50 degrees (180 - 30 - 100 = 50).

Front

What is the sum of the angles in any triangle?

Back

The sum of the angles in any triangle is always 180 degrees.