Balancing Act: The Truth behind the Equals Sign
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Because there are no totals in this problem, and the focus is on the equivalence/balance of the sides of the “equation”, this problem is useful in introducing the concept of substituting one variable for another. For example: one orange hexagon is equivalent to two stars, and thus one can be substituted for another. Once the problems that are in the article are completed, first year Algebra teachers can then go a step further, and create equations where the substitutions can be applied. Two blue cubes and green oval equal how many cylinders? This was great for a day before a holiday, not only can the teacher create problems for everyone to solve, but so can other students, always a fun activity in my classes.
Putting a twist on a popular mathematical tool, this collection
of activities shows how putting a number 1 in the bottom-left cell and a 100 in
the top-right cell can better support student reasoning.