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Videos, worksheets, solutions and activities to help Algebra students learn how to subtract rational expressions.

Rational Expressions 6 - Subtracting with Common Denominator

How to subtract rational expressions that already have a common denominator, and how to simplify if it is possible to cancel.

Students learn that when subtracting rational expressions, the first step is to change the minus sign between the terms to a plus sign, and change all the signs across the numerator of the following term.

Next, factor each of the denominators, if possible, then give each term a common denominator by multiplying the numerator and denominator of each term by the appropriate value.

Next, add across the numerators and keep the denominators the same. Finally, factor the resulting numerator, if possible, to determine if the rational expression can be reduced.

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