Lines and Angles Vocabulary

the point where two lines meet

• vertex

• intersection

• angle

• line segment

a part of a line that has a fixed starting point and goes on forever in one direction

• line

• segment

• ray

• plane

a line that divides an angle into two equal parts

• angle bisector

• angle divider

• angle separator

• angle cutter

lines that cross at right angles

• parallel

• intersecting

• perpendicular

• tangential

two angles that add up to 180 degrees

• complementary angles

• adjacent angles

• supplementary angles

• vertical angles

a line that goes on forever in both directions

• line

• segment

• ray

• curve

the space between two intersecting lines

• angle

• line

• point

• plane

lines that cross (but do not form right angles)

• intersecting

• parallel

• perpendicular

• converging

an angle that is exactly 180 degrees

• acute angle

• obtuse angle

• straight angle

• right angle

two angles that add up to 90 degrees

• complementary angles

• supplementary angles

• vertical angles

• adjacent angles