Internal & External Angles of Triangles

Front

What is the sum of the internal angles of a triangle?

Back

180 degrees

Front

What is an internal angle in a triangle?

Back

An angle formed by two sides of a triangle that is inside the triangle.

Front

What is an external angle in a triangle?

Back

An angle formed between one side of a triangle and the extension of an adjacent side.

Front

If one angle of a triangle is 60 degrees and another is 70 degrees, what is the third angle?

Back

50 degrees

Front

What are remote interior angles?

Back

Angles that are not adjacent to a given exterior angle but are inside the triangle.

Front

How do you find the measure of an external angle?

Back

The measure of an external angle is equal to the sum of the two remote interior angles.

Front

What is the relationship between the internal and external angles of a triangle?

Back

Each external angle is equal to the sum of the two opposite internal angles.

Front

If a triangle has angles measuring 45 degrees and 55 degrees, what is the measure of the third angle?

Back

80 degrees

Front

What is the formula to find the missing angle in a triangle?

Back

180 - (sum of the known angles) = missing angle.

Front

What are corresponding angles?

Back

Angles that are in the same position on different parallel lines cut by a transversal.