Angle Relationships

Front

What are vertical angles?

Back

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

Front

Which angles are considered vertical angles?

Back

Angles that are opposite each other at the intersection of two lines, such as ∠COB and ∠AOD.

Front

What is the relationship between supplementary angles?

Back

Supplementary angles are two angles whose measures add up to 180 degrees.

Front

If two angles are supplementary and one angle measures 2x and the other measures 10x, what are their measures?

Back

The angles measure 30° and 150°.

Front

What are complementary angles?

Back

Complementary angles are two angles whose measures add up to 90 degrees.

Front

If two angles are complementary and one angle measures x, what is the measure of the other angle?

Back

The other angle measures 90° - x.

Front

What is the equation for finding the measure of angles that are supplementary?

Back

The equation is: angle1 + angle2 = 180°.

Front

What is the equation for finding the measure of angles that are complementary?

Back

The equation is: angle1 + angle2 = 90°.

Front

If vertical angles are always congruent, what can we say about their measures?

Back

The measures of vertical angles are equal.

Front

How do you solve for x in the equation 2x - 6 + 7x + 4 = 90?

Back

Combine like terms to get 9x - 2 = 90, then solve for x.