Geometry Basics

Front

parallel lines

Back

lines in the same plane that never intersect

Front

line

Back

a straight path that goes on forever in opposite directions

Front

line segment

Back

part of a line that has two endpoints

Front

perpendicular

Back

lines, line segments, or rays that form right angles

Front

point

Back

a location in a plane usually shown by a dot

Front

intersecting lines

Back

lines that pass through the same point

Front

ray

Back

a part of a line with one endpoint and that goes forever in one direction

Front

angle

Back

a figure formed when two rays have the same endpoint

Front

right angle

Back

an angle that is a square corner OR 90 degrees

Front

acute angle

Back

an angle that is open less than a right angle (less than 90 degrees)