Math = Love: Solving Equations with Variables on One Side of the Equal Sign

## Saturday, October 24, 2015

### Solving Equations with Variables on One Side of the Equal Sign

I keep going back and forth with my approach to Algebra 1.  Some years, I decide to review everything to make sure my students are on the same page.  Other years, I decide to just jump in with new material.  This year is a review everything sort of year.  And, I feel sooooooo behind.  I'm so ready to get to some slope and graphing!

If you could see my district's 8th grade test scores, you'd understand, I think, why I decided to start off this year with review.  Algebra 1 is high-stakes in Oklahoma.  Students must pass the end-of-instruction exam in order to be eligible to graduate.  My students come to me having taken 5 standardized math tests.  None of these had any repercussions.  If they scored unsatisfactory, they still moved on to the next higher math class.  Then, they get to me and things matter all of a sudden.

Okay.  Enough complaining.  You guys are mostly teachers.  I'm just preaching to the choir.

Notes for solving equations with variables on one side of the equal sign:

I tried to connect making ones and making zeros to actions I could do to their bank account.  I can afford to add 0 dollars to each student's bank account.  And, I can afford to multiply each student's bank account by one.  +5 and -5 make a zero.  Similarly, if I add five dollars to their bank account and take five dollars out, their bank account isn't affected.

Throughout this unit, students hear me say over and over and over and over, "If I do it to one side of the equation, I have to do it to the other side of the equation!"

Some practice problems :D  I made sure to give them plenty more practice with the distributive property and combining like terms!

Two changes I've made this year:

* Giving kids word problems on their quizzes.  We've always practice word problems in class, but I've never given them on quizzes.  Then, I wonder why students freak out when they see them on the EOI exam.  This summer, I decided if I put them on the quizzes, then I had to prepare students for them.  I realize most people already do this.  Guess I'm just late to the game...

* Having kids check the solution they found with their scientific calculator.

I have them use the store key to store the solution they got as x.  Then, they type in the side of the original equation with x in it.  The calculator display *should* match the other side of the equal sign if they did everything correctly.

My students aren't allowed to use calculators on their middle school exams, so I also have the job of getting them comfortable with our calculators.  Many are still hesitant to use them because it's ingrained in their minds that tests = no calculator.  They are constantly shocked.  "You mean, you want us to use the calculator?!?"  Ummm...yeah.

I was always taught to check equations manually, but my students are still struggling so much with positives and negatives and multiplying and dividing that this just makes more sense.  I know if I tell them to check by hand, they'll more than likely just skip the checking step.  But, they get really excited to see the calculator tell them their solution is correct.

Here's a picture of the tutorial in their calculator tutorial pocket:

1. I teach kids to draw a "math wall of doom" - the name doesn't have much significance, but it helps things stick - it's a line through the equal sign that goes all the way to the end of the problem. That way they can really see the "if I do it to one side, I do it to the other." It's a good visual of what the "other side" means. I do teach resource room, but struggles are struggles!

1. I LOVE this idea!