Introduction

The definition of parallel lines is lines that never intersect. Notice that the beach towel in the picture is an example of parallel lines. Can you think of another example of parallel lines?

beach towell with parallel lines

Lesson Objectives

Following successful completion of this lesson, students will be able to...

  • Determine whether two lines are parallel given their equations or graphs
  • Write the equation of a line in slope intercept given the lines are parallel and passing through a given point

Essential Questions

  • What does the slope a line tells you about the line?
  • How are parallel lines and perpendicular line different?
  • What does the equation of a line tell you about graph of the line?

Enduring Understandings

  • The slope of a linear equation represents a constant rate of change.
  • Linear relationships can be defined on the coordinate plane.
  • The characteristics of linear equations and their graphs are useful in solving real-world problems.
  • Slope can be used to prove that two lines are parallel or perpendicular.
  • Slope can be used to prove that two lines are parallel or perpendicular.

The above objectives correspond with the Alabama Course of Study: Geometry standard: 33.