Triangle Angle Sum & Exterior Angle Theorem

Front

What is the Triangle Angle Sum Theorem?

Back

The Triangle Angle 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, what type of triangle is it?

Back

It is a right triangle.

Front

What is the measure of the third angle in a triangle if the other two angles are 50 degrees and 60 degrees?

Back

70 degrees (180 - 50 - 60 = 70).

Front

What is the Exterior Angle Theorem?

Back

The Exterior Angle Theorem states that the measure of an exterior angle of a triangle is equal to the sum of the measures of the two opposite interior angles.

Front

If an exterior angle measures 120 degrees, what is the sum of the two opposite interior angles?

Back

120 degrees.

Front

How do you find the measure of an unknown angle in a triangle?

Back

Subtract the sum of the known angles from 180 degrees.

Front

What is the relationship between the angles in a triangle and a straight line?

Back

The angles on a straight line sum up to 180 degrees.

Front

If angle A is 40 degrees and angle B is 70 degrees, what is angle C in triangle ABC?

Back

Angle C is 70 degrees (180 - 40 - 70 = 70).

Front

What equation would you use to find an unknown angle x if the other angles are 30 and 50 degrees?

Back

x + 30 + 50 = 180.

Front

If x + 38 = 90, what is the value of x?

Back

x = 52.