Lines & Angles Flashcard for 4th Grade 11/15/24

Front

What is a line?

Back

A line is a straight path that extends infinitely in both directions and has no endpoints.

Front

What is a ray?

Back

A ray is a part of a line that has a starting point but no endpoint, extending infinitely in one direction.

Front

What is a line segment?

Back

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

Front

What is an angle?

Back

An angle is formed by two rays that share a common endpoint, called the vertex.

Front

What type of angle is exactly 90 degrees?

Back

A right angle.

Front

What type of angle is less than 90 degrees?

Back

An acute angle.

Front

What type of angle is greater than 90 degrees but less than 180 degrees?

Back

An obtuse angle.

Front

What type of angle is exactly 180 degrees?

Back

A straight angle.

Front

What are parallel lines?

Back

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

Front

What are perpendicular lines?

Back

Perpendicular lines are lines that intersect at a right angle (90 degrees).