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Multiply Rational Expressions 4 Factor

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    These are the factored forms, great work for getting at least half of these
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    right. If you really struggled with these, I would go back and review factoring.
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    Try and get in some more practice before moving on. If you only missed one or
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    two, then see if you can find your mistakes by looking at your factors. If you
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    can't find your mistakes, then continue watching this solution to see where your
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    reasoning went wrong. The greatest common factor for these three terms is 1. So
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    let's use factoring by grouping to get our two factors. We want factors of
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    negative 30 that sum to negative one. The factors are negative 6 and positive 5.
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    Then we can use factoring by grouping to get the factors of 3 x plus 1. And five
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    x minus two, this is our first numerator. For the denominator, we want to find
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    factors of negative 20 that sum to positive eight. The factors would be positive
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    ten and negative two. We use factoring by grouping to get our denominator of two
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    x plus five, times two x minus one here. Next we factor this trinomial. [The
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    greatest common factor for each term is one, so we need to find factors of
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    negative sixty that's sum to negative seven. We don't need to factor out a GCF.
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    These two factors are negative twelve and positive five. They might have been
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    tough to find. We use factoring by grouping to get two X plus five times X minus
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    six. And this is what we put in our numerator. For our second denominator, we
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    want to find factors of negative 30, that's sum to positive 13. We use
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    fracturing by grouping to get our factors of x plus 3 and 5x minus 2. And now
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    we're done factoring and we're ready to simplify.
Title:
Multiply Rational Expressions 4 Factor
Video Language:
English
Team:
Udacity
Project:
MA006 - Visualizing Algebra
Duration:
01:28
Cogi-Admin added a translation

English subtitles

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