Triangle Sum and Exterior Sum

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 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 does the Exterior Angle Theorem state?

Back

The Exterior Angle Theorem states that the measure of an exterior angle is equal to the sum of the measures of the two remote interior angles.

Front

If one angle of a triangle is 90 degrees, what is the sum of the other two angles?

Back

The sum of the other two angles is 90 degrees, since the total must equal 180 degrees.

Front

What is a remote interior angle?

Back

A remote interior angle is an interior angle of a triangle that is not adjacent to a given exterior angle.

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 degrees.

Front

What is the relationship between corresponding angles when two parallel lines are cut by a transversal?

Back

Corresponding angles are equal when two parallel lines are cut by a transversal.

Front

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

Back

Each angle in an equilateral triangle measures 60 degrees.

Front

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

Back

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

Front

What is the definition of an interior angle?

Back

An interior angle is an angle formed inside a triangle by two sides.