Reflection: Modeling Graph Inequalities on a Number Line - Section 1: Introduction


All of my core class students have an intervention math class twice a week for 45 minutes.  I work with the Tier 2 students in grades 6-8.  The Tier 1 students work with the 8th grade math teacher, Ms. C.  

Well Ms. C., unbeknownst to me, had already taught graphing inequalities on the number line to my students in her Tier 1 group - that's about 10-12 students in each core class.  Ms. C. insisted that they draw the endpoint and then draw a bold ray in the proper direction down the number line.  I tend to draw the endpoint and then draw a curvy arrow in the proper direction.  Well these students were in an uproar!  "Ms.  C. said you have to do it like this!"

After telling several jokes at Ms. C's expense (ha ha!), including how much shading she'll require when they learn in 8th grade to graph these solutions on the coordinate plane (Students: Huh?  Me: Bwa ha ha!), I acknowledged that her method might be the best way to model the solution to an inequality but it is okay to draw the model as I draw it.  I showed them another variation that I have seen where the ray is drawn above the number line.   

Here is an example of the three ways of graphing.

  Modeling: That's Not How Ms. C. Taught This
Loading resource...

Graph Inequalities on a Number Line

Unit 4: Expressions and Equations
Lesson 11 of 20

Objective: SWBAT graph inequalities as open and closed point rays on a number line

Big Idea: Number lines represent solutions to inequalities (and equations).

  Print Lesson
17 teachers like this lesson
Math, Number lines , Expressions (Algebra), graph inequalities, equation
  45 minutes
Similar Lessons
Word Problems with Equations
7th Grade Math » Equations
Big Idea: Lots of steps...that's okay! Identify the variable and then re-read the problem to determine what is happening to the variable.
Elon, NC
Environment: Suburban
Heather Stephan
Solving Inequalities
7th Grade Math » Equations and Inequalities
Big Idea: Do students understand what the solution to an inequality is?
Columbus, OH
Environment: Urban
Jada Jackson
Solving Compound Inequalities
Algebra I » Expressions, Equations, and Inequalities
Big Idea: Students recognize the meaning of "and" as an intersection of solutions, and "or" meaning that only one of the inequalities have to be true.
Rogers, AR
Environment: Rural
Rhonda Leichliter
Something went wrong. See details for more info
Nothing to upload