Angle Relationships & Triangle Sum

Front

What are corresponding angles?

Back

Corresponding angles are pairs of angles that are in the same position on two parallel lines cut by a transversal. They are equal in measure.

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

If two angles are supplementary, what is their sum?

Back

The sum of two supplementary angles is 180 degrees.

Front

If two angles are complementary, what is their sum?

Back

The sum of two complementary angles is 90 degrees.

Front

What is the measure of an angle if it is 90 degrees?

Back

An angle that measures 90 degrees is called a right angle.

Front

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

Back

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

Front

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

Back

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

Front

What is the value of x if angle A = 60° and angle B = x° in a triangle?

Back

If angle A = 60° and angle B = x°, then x = 120° (since the sum of angles in a triangle is 180°).

Front

What is the value of y if angle 1 and angle 2 are supplementary and angle 1 = 70°?

Back

If angle 1 = 70°, then angle 2 = 110° (since supplementary angles sum to 180°).

Front

What are vertical angles?

Back

Vertical angles are the angles opposite each other when two lines intersect. They are equal in measure.