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The most useful rules of basic algebra,
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Howdy! Here are a few very handy rules of algebra. These basic rules are useful for everything from figuring out your gas mileage to acing your next math test — or even solving equations from the far reaches of theoretical physics. Happy calculating!

Algebra Rule 8

Split a fraction with an addition in the numerator into two fractions

$${(a+b) \over c} = {a \over c} + {b \over c}$$
Description:

This is simply a result of the fact that two fractions with common denominators can be added by adding the numerators and leaving the denominator unchanged. It is intuitively simple: 1 third plus 2 thirds is 3 thirds. The reverse is also true: 3 thirds minus 2 thirds equals 1 third.

$${(1+2) \over 4} = {3 \over 4} = {1 \over 4} + {2 \over 4}$$
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