Lines, Classifying Polygons, and Symmetry

Front

What are perpendicular lines?

Back

Lines that intersect at a right angle (90 degrees).

Front

What are parallel lines?

Back

Lines that run in the same direction and never meet, no matter how far they are extended.

Front

What are intersecting lines?

Back

Lines that cross each other at any angle.

Front

What is an acute angle?

Back

An angle that measures less than 90 degrees.

Front

What is a right angle?

Back

An angle that measures exactly 90 degrees.

Front

What is an obtuse angle?

Back

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

Front

What is symmetry?

Back

A property where one shape becomes exactly like another when you flip, slide, or turn it.

Front

What is a line of symmetry?

Back

A line that divides a shape into two identical parts that are mirror images of each other.

Front

How many lines of symmetry does a square have?

Back

A square has 4 lines of symmetry.

Front

How many lines of symmetry does a circle have?

Back

A circle has an infinite number of lines of symmetry.