I shared here part 1 of our unit on systems of equations -solving by graphing and by substitution.

##### Elimination

I started this unit with the following warm-up.

Then I followed it up with this notice/wonder.

One of my students this past year noticed that, “These are like the problems we did for warm-up.” I love when my students notice connections between the warm-up and the lesson for the day and that I’m not just having them do random stuff.

I was really pleased with how this led nicely into the lesson for the day. Students noticed that in each problem there was a zero. They were able to tell me why that happened. When I told them that this is another method for solving systems of equations called elimination, at least someone in each class was able to explain why they thought that elimination was a good name for this method.

It had been a while since we had done Vertical Non-Permanent Surfaces, and these problems work great for that.

##### Choosing Method

The last part of this unit was having students choose the best/most efficient method for solving a system of equations.

I started with this Desmos Activity. I didn’t have students solve the systems the first day. I wanted them to just think through what method they would want to use to solve each. The next day they actually solved some of the systems.

I love this Desmos Activity from Paul Jorgens.

I’ve uploaded some of the worksheets and notes I used from this unit here.