Triangle Angle Relationships and Properties

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°.

Front

If one angle of a triangle measures 75° and another measures 19°, what is the measure of the third angle?

Back

86°

Front

Will the angles 30°, 60°, and 90° form a triangle?

Back

Yes, because the sum of the angles is 180°.

Front

What is the measure of the missing angle in a triangle if the other two angles are 30° and 110°?

Back

40°

Front

What is the measure of the third angle in a triangle with angles measuring 34° and 101°?

Back

45°

Front

What is the measure of an angle in a triangle if the other two angles are 50° and 80°?

Back

50°

Front

What is the relationship between the angles in a right triangle?

Back

In a right triangle, one angle measures 90°, and the sum of the other two angles is 90°.

Front

If a triangle has angles measuring 40° and 60°, what is the measure of the third angle?

Back

80°

Front

What is the definition of an acute triangle?

Back

An acute triangle is a triangle where all three angles are less than 90°.

Front

What is the definition of an obtuse triangle?

Back

An obtuse triangle is a triangle that has one angle greater than 90°.