Geometry Ch. 1 Sect. 1

11 terms

undefined term

words that dont have a formal definition but there is an agreement about what they mean

point

represented by a dot, has no dimension

line

infinite length, one dimension, represented by a bar with 2 arrow heads

plane

has 2 dimensions, its represented by a parallelogram, extends without end in 2 directions

colinear

points that lay on the same line (must have 3 or more points to be colinear)

coplanar

points that lay on the same plane

line segment

consists of 2 endpoints A and B and all the points in between them (represented by a bar over the name)

ray

contains one endpoint and all pints on the line go in 1 direction (represented by a bar with one arrowhead going to the right over the name/ the first letter in the name is endpoint)

opposite ray

if point C lies on line AB between A and B, then CA and CB are opposite lines (together the 2 new names make a line)

types of intersection of a line and plane

1. no intersection 2. one point (line goes through plane) 3. infinite number of points ( line on top of plane)

types of intersection of two planes

1. no intersection 2. one line