Angle Relationships

Front

What are vertical angles?

Back

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

Front

What is the measure of the missing angle if one angle is 39°?

Back

The missing angle is 141° because the sum of angles on a straight line is 180°.

Front

Identify the alternate interior angle to angle 3.

Back

The alternate interior angle to angle 3 is angle 5.

Front

What are alternate interior angles?

Back

Alternate interior angles are pairs of angles that are on opposite sides of a transversal and inside the two lines.

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.

Front

If angle 6 and angle 7 are vertical angles, what can be said about their measures?

Back

Angle 6 and angle 7 are equal in measure.

Front

What is the sum of angles on a straight line?

Back

The sum of angles on a straight line is 180°.

Front

If two parallel lines are cut by a transversal, what type of angles are formed?

Back

Two pairs of alternate interior angles, two pairs of corresponding angles, and two pairs of same-side interior angles are formed.

Front

What is the relationship between alternate exterior angles?

Back

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

Front

How do you find the measure of an unknown angle when given one angle?

Back

Subtract the known angle from 180° if they are on a straight line, or use the properties of vertical or corresponding angles.