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Evaluating expressions with unknown variables

2 videos
2 skills
When solving equations, there is a natural hunger to figure out what an unknown is equal to. This is especially the case if we want to evaluate an expression that the unknown is part of. This tutorial exposes us to a class of solvable problems that challenges this hunger and forces us to be the thinking human beings that we are! In case you're curious, these types of problems are known to show up on standardized exams to see if you are really a thinking human (as opposed to a robot possum).

Evaluating expressions where individual variable values are unknown

VIDEO 4:39 minutes
Working through a few examples where we need to evaluate an expression, but we don't know the individual variable values

Evaluating expressions with unknown variables 2

VIDEO 3:00 minutes
A few more examples where we are asked to evaluate an expression with multiple uknown variables

Expressions with unknown variables

Multiplying variable expressions given their sums.