Slide the sliders to set the values of the variables. Then click the GO button. You will see that the commutative property will serve you up the same answer, left and right side, no mater where you set the sliders.
This project shows the commutative property of multiplication. Instead of letters it uses pictures for variables. Use the sliders to quickly pick a value for each variable. Then hit the go button and you will see, the same answer calculated on each side, naturally. The calculations could be done a lot of more quickly of course, but I put is a few delays to add a sense of drama, and to make sure that the user can see what is happening. Look for more real number property demos coming soon.