Basic Geometry Vocabulary

Front

What is a flat surface made up of points that has two dimensions and extends without end?

Back

Plane

Front

What does a line with one endpoint and extends infinitely in one direction represent?

Back

Ray

Front

What is a line that has one dimension, represented by a line with two arrowheads, and extends without end?

Back

Line

Front

Which symbol represents a line that extends in both directions without end?

Back

↔

Front

What do you call coplanar lines that do not intersect?

Back

Parallel Lines

Front

What is the term for two lines that intersect at a right angle?

Back

Perpendicular Lines

Front

What do you call a part of a line that has two endpoints?

Back

Line Segment

Front

What is the term for a point that divides a segment into two equal parts?

Back

Midpoint

Front

What do you call angles that add up to 90 degrees?

Back

Complementary Angles

Front

What do you call angles that add up to 180 degrees?

Back

Supplementary Angles