Interior and Exterior Angles of Triangles

Front

What is the sum of the interior angles of a triangle?

Back

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 are corresponding angles?

Back

Corresponding angles are angles that are in the same position on two parallel lines cut by a transversal.

Front

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

Back

To find the measure of an unlabeled angle in a triangle, subtract the sum of the known angles from 180 degrees.

Front

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

Back

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

Front

What is the definition of an acute angle?

Back

An acute angle is an angle that measures less than 90 degrees.

Front

What is the definition of an obtuse angle?

Back

An obtuse angle is an angle that measures more than 90 degrees but less than 180 degrees.

Front

What is the definition of a right angle?

Back

A right angle is an angle that measures exactly 90 degrees.

Front

What is the formula for finding the measure of an angle in a triangle when two angles are known?

Back

The measure of the unknown angle can be found using the formula: Unknown Angle = 180 - (Angle 1 + Angle 2).

Front

What is the difference between interior and exterior angles?

Back

Interior angles are inside the triangle, while exterior angles are formed outside the triangle by extending one of its sides.