Interior/Exterior Angles of Triangles

Front

What are interior angles of a triangle?

Back

Interior angles are the angles formed inside a triangle, which are the angles between the sides of the triangle.

Front

What are exterior angles of a triangle?

Back

Exterior angles are the angles formed outside a triangle when one side is extended. Each exterior angle is equal to the sum of the two remote interior angles.

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

What are remote interior angles?

Back

Remote interior angles are the two interior angles of a triangle that are not adjacent to a given exterior angle.

Front

If one angle of a triangle is 90 degrees, what are the other two angles?

Back

The other two angles must add up to 90 degrees, since the sum of all angles in a triangle is 180 degrees.

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 an exterior angle and its remote interior angles?

Back

An exterior angle is equal to the sum of its two remote interior angles.

Front

If angle A = 38 degrees and angle B = 57 degrees, what is angle C?

Back

Angle C = 180 - (38 + 57) = 85 degrees.

Front

What is the value of x if angle A + angle B + angle C = 180 degrees?

Back

x = 180 - (sum of angles A and B).

Front

What is the measure of an angle if it is complementary to 25 degrees?

Back

The angle is 90 - 25 = 65 degrees.