Unit 5A - 5.1.1 Vocab Practice

Front

What are parallel lines?

Back

Lines in a plane that never meet and are always the same distance apart.

Front

What is an acute angle?

Back

An angle that measures less than 90 degrees.

Front

What is a straight angle?

Back

An angle that measures exactly 180 degrees.

Front

What is a right angle?

Back

An angle that measures exactly 90 degrees.

Front

What is a ray?

Back

A part of a line that has one endpoint and extends infinitely in one direction.

Front

What are intersecting lines?

Back

Lines that cross each other at one point.

Front

What are perpendicular lines?

Back

Lines that intersect to form right angles.

Front

What is an obtuse angle?

Back

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

Front

What is a line segment?

Back

A part of a line that has two endpoints.

Front

What is the sum of angles in a triangle?

Back

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