Now lets look at a new model for solving equations, one that works in situations where backtracking doesn't.
The model of bags and blocks focuses on the idea of balance. Each bag holds an unknown number of blocks (eventually represented by a variable). Each bag in the same problem must hold the same number of blocks, just as a variable in an equation must stand for the same number every time it is used.
The challenge is to solve a series of problems by figuring out how many blocks are in each bag. Encourage participants to solve the problems by removing the same thing from each side of the scale, which is comparable to the more formal process of doing the same thing to both sides of an equation.
Groups: Work in pairs on Problems C1-C7.
<< back to Part C: Balance Puzzles and Equations