Algebra here we come!

Variables have entered our math the last couple of weeks.  Yep, math is now numbers and operational signs AND letters :-)

These boys show how they counted the number of tiles in this picture frame, without actually counting each tile.  This was our introduction to writing expressions like: 4(10) - 4 and 10+10+8+8.

Here we are finding out how many tiles would be in a square picture frame of ANY size.  We used a variable to represent the changing side length of the picture frame:  4(x) - 4 and x+x+x-2+x-2.