6.6 Addition and Subtraction of Fractions

  • Lowest Common Denominator • Addition and Subtraction of Fractions • Complex Fractions

From arithmetic, recall that the sum (or difference) of a set of fractions that all have the same denominator is the sum (or difference) of the numerators divided by the common denominator.

Because algebraic expressions represent numbers, this fact is also true in algebra. Addition and subtraction of such fractions are illustrated in the following example.

EXAMPLE 1 Combining basic fractions

  1. 59 + 29 − 49 = 5 + 2 − 49 ← sum of numerators← same denominators = 39 = 13← final result in lowest terms


When ...

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