Adding rational expressions with different denominators 2

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Taught by YourMathGal
  • Currently 4.0/5 Stars.
5807 views | 1 rating
Part of video series
Meets NCTM Standards:
Lesson Summary:

In this lesson, students learn how to add and subtract algebraic fractions by getting a common denominator. The first step is to rewrite each fraction so that each denominator is factored. Then, if any factors are missing, you need to multiply the numerator and denominator of the fraction by those missing factors. Once you have a common denominator, you can add or subtract the numerators, simplifying them if necessary. Finally, check to see if you can factor and cancel out anything in the numerator and denominator.

Lesson Description:

Shows how to add and subtract algebraic fractions by getting a common denominator.

More free YouTube videos by Julie Harland are organized at http://yourmathgal.com

Questions answered by this video:
  • How do you add and subtract rational expressions with different denominators?
  • How do you subtract 5/(x + 2) - 2x/(x^2 - 4) by finding the least common denominator?
  • What is 2x/(x^2 + 5x + 6) + 3/(x^2 - 9)?
  • What is the jealousy method for finding a least common denominator and how is it used to add fractions?
  • How do you add 7/(3x - 2) + 6x/(2 - 3x) when the denominators are opposites of each other?
  • How do you subtract 7/(x - 4) - 3/(4 - x) if the denominators are opposites of each other?
  • Staff Review

    • Currently 4.0/5 Stars.
    This lesson does many more practice problems for finding the least common denominator of 2 rational expressions and then after giving each fraction this denominator, adding or subtracting the two algebraic fractions. This is a great lesson with great explanations.