CM: test 4 (Vertical <,Triangle Sum Theorem)

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 one angle of a triangle is 90 degrees and another is 45 degrees, what is the measure of the third angle?

Back

The third angle measures 45 degrees, since 90 + 45 + x = 180.

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 vertical angles?

Back

Vertical angles are equal; when two lines intersect, the opposite angles formed are congruent.

Front

If two angles are supplementary, what is their sum?

Back

The sum of two supplementary angles is 180 degrees.

Front

What is the measure of Angle 1 if it is supplementary to a 161-degree angle?

Back

Angle 1 measures 19 degrees, since 180 - 161 = 19.

Front

What is the formula for finding the measure of an exterior angle of a triangle?

Back

The measure of an exterior angle is equal to the sum of the measures of the two non-adjacent interior angles.

Front

If a triangle has angles measuring 30 degrees and 60 degrees, what is the measure of the third angle?

Back

The third angle measures 90 degrees, since 30 + 60 + x = 180.

Front

What is the definition of complementary angles?

Back

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

Front

If one angle measures 45 degrees, what is the measure of its complement?

Back

The complement measures 45 degrees, since 90 - 45 = 45.