Angles and Triangles

Front

What is an angle?

Back

An angle is formed by two rays (sides of the angle) that share a common endpoint (the vertex).

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 corresponding angles?

Back

Corresponding angles are pairs of angles that are in the same position on two parallel lines cut by a transversal.

Front

What is a transversal?

Back

A transversal is a line that intersects two or more lines at different points.

Front

What is the measure of a right angle?

Back

A right angle measures 90 degrees.

Front

What is an acute angle?

Back

An acute angle is an angle that measures less than 90 degrees.

Front

What is an obtuse angle?

Back

An obtuse angle is an angle that measures more than 90 degrees but less than 180 degrees.

Front

What is a straight angle?

Back

A straight angle measures exactly 180 degrees.

Front

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

Back

To find the measure of an unknown angle in a triangle, subtract the sum of the known angles from 180 degrees.

Front

What is the relationship between angles formed by parallel lines and a transversal?

Back

Angles formed by parallel lines and a transversal include corresponding angles, alternate interior angles, and same-side interior angles, which have specific relationships (equal or supplementary).