Triangle Properties and Angle Relationships

Front

What are supplementary angles?

Back

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

Front

If angle A is 82°, what is the measure of its supplementary angle?

Back

98° (180° - 82° = 98°)

Front

What are complementary angles?

Back

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

Front

If angle B is 37°, what is the measure of its complementary angle?

Back

53° (90° - 37° = 53°)

Front

What is the Triangle Inequality Theorem?

Back

The Triangle Inequality Theorem states that the sum of the lengths of any two sides of a triangle must be greater than the length of the third side.

Front

If one side of a triangle measures 4 cm, what can be the measures of the other two sides?

Back

The other two sides must be greater than 4 cm and less than 8 cm combined.

Front

What are vertical angles?

Back

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

Front

If angle C is 48°, what is the measure of its vertical angle?

Back

48° (Vertical angles are equal.)

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

If angle D is 60° and angle E is 70°, what is the measure of angle F in triangle DEF?

Back

50° (180° - 60° - 70° = 50°)