FLASHCARD 2: Angles in Triangles

Front

What is the Triangle Sum Theorem?

Back

The Triangle Sum Theorem states that the sum of all angles in a triangle is 180°.

Front

Find the value of angle T if angle A = 54° and angle B = 72°.

Back

Angle T = 180° - (54° + 72°) = 54°.

Front

What is the measure of angle x if angle y = 45° and angle z = 90°?

Back

Angle x = 180° - (45° + 90°) = 45°.

Front

If one angle of a triangle is 60° and another is 80°, what is the third angle?

Back

Third angle = 180° - (60° + 80°) = 40°.

Front

What is the definition of complementary angles?

Back

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

Front

What is the definition of supplementary angles?

Back

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

Front

If angle A = 30° and angle B = 60°, what is angle C in triangle ABC?

Back

Angle C = 180° - (30° + 60°) = 90°.

Front

What is the measure of an exterior angle of a triangle?

Back

An exterior angle of a triangle is equal to the sum of the two opposite interior angles.

Front

If angle A = 45° and angle B = 45°, what is angle C?

Back

Angle C = 180° - (45° + 45°) = 90°.

Front

What is the relationship between the angles in an isosceles triangle?

Back

In an isosceles triangle, the angles opposite the equal sides are equal.