Geometry 1.2 Points. Lines and Planes

Geometry 1.2Points. Lines and Planes

Points • Basic Unit of Geometry • Has no size • Named using capital letters • Points are written as capital letters A, B, C

What Points Look Like A S B M R

If we get a lot of points together and they are straight we make a line! B C S P M L

Lines • Are made of an infinite number of points • Extend in both directions FOREVER • Named by two points on the line • Or with a lowercase cursive letter • The name is written with a symbol AB SV KT

What Lines Look Like d S M G

Vocabulary • Collinear = • points on the same line • Noncollinear = • Not on the same line

Collinear/Noncollinear d S l H M Q G

Rays • Are lines that end on one side • Extend in one direction FOREVER • Named by the endpoint and one other point on the ray • The name is written with a symbol CB KM UV

What do rays look like V K M C U V X

Line Segment • The chunk of line between two points • Could be part of a line or ray or alone • Named by the endpoints • The name is written with a symbol BH DG PV

What do Line segments look like V K M C U V X

Plane • Flat surface • Extends FOREVER • Named by three points in the plane • Or by an uppercase cursive letter • The name is written like this ABC JKM R

More Vocabulary • Coplanar = • points on the same • Noncoplanar = • Not on the same plane plane

What do planes look like R V M K C U

1.23-27

Geometry 1.2 Points. Lines and Planes