Page:Philosophy and Fun of Algebra.djvu/23

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CHAPTER III
SIMULTANEOUS PROBLEMS

It often happens that two or three problems are so entangled up together that it seems impossible to solve any one of them until the others have been solved. For instance, we might get out three answers of this kind:—

x equals half of y;
y equals twice x;
z equals x multiplied by y.

The value of each depends on the value of the others.

When we get into a predicament of this kind, three courses are open to us.

We can begin to make slap-dash guesses, and each argue to prove that his guess is the right one; and go on quarrelling; and so on; as I described people doing about arithmetic before Algebra was invented.

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