Angles and Triangles

Front

What is an angle?

Back

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

Front

What is a triangle?

Back

A triangle is a polygon with three edges and three vertices.

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 is the formula for the sum of interior angles in a polygon?

Back

The formula is 180(n−2), where n is the number of sides.

Front

What are corresponding angles?

Back

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

Front

What are alternate interior angles?

Back

Alternate interior angles are angles that lie between two parallel lines on opposite sides of a transversal.

Front

What is the relationship between alternate interior angles?

Back

Alternate interior angles are congruent when the lines are parallel.

Front

What is the sum of the exterior angles of any polygon?

Back

The sum of the exterior angles of any polygon is always 360 degrees.

Front

What is a right triangle?

Back

A right triangle is a triangle that has one angle measuring 90 degrees.

Front

What is an acute triangle?

Back

An acute triangle is a triangle where all three angles are less than 90 degrees.