About Geometry Worksheet Assignment 1.9:    

 

Assignment 1.9 is an introduction to the use of slopes to determine whether lines in the coordinate plane are parallel.

 

Prerequisite Skills: Find slopes of lines on the coordinate plane by counting rise and run.  Find slopes of lines using the slope formula (Assignment 1.8).

 

Postulate:  Lines with the same or equal slopes are parallel. 

                        Lines with slopes that are not the same or are not equal are not parallel.