Parallèle: Même Pente!

In grade 10 my class has learned a call and answer….when I call out “parallèle” they will reply with “même pente” (same slope). We had not talked about this for a while, and were doing some review work in groups at the boards, and I flipped to this slide to end the class. The challenge is to find which figure number will have the same perimeter.

I was very impressed to see their way of working through the problem. This group made equations, then realized the slopes are the same, so they are parallel and will not intersect.

This group made a table of values for each pattern and noticed that the first differences are the same, so the slopes are the same, so they are parallel.

I am very pleased that even after not talking about it for a few days, that students have remembered that parallel lines have the same slope!