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 three-sided polygon.

Front

What are the types of angles?

Back

The types of angles are acute (less than 90°), right (exactly 90°), and obtuse (greater than 90° but less than 180°).

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 right angle?

Back

A right angle is an angle that measures exactly 90 degrees.

Front

What is a line segment?

Back

A line segment is a part of a line that has two endpoints.

Front

What are intersecting lines?

Back

Intersecting lines are lines that cross each other at a point.

Front

What is a vertex in a triangle?

Back

A vertex is a point where two sides of a triangle meet.

Front

What is the sum of the angles in a triangle?

Back

The sum of the angles in a triangle is always 180 degrees.