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Math Help - Factoring

  1. #1
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    Factoring

    Factor: 3x^2 - 11x + 6

    Kasey
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  2. #2
    is up to his old tricks again! Jhevon's Avatar
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    Quote Originally Posted by flippin4u View Post
    Factor: 3x^2 - 11x + 6

    Kasey
    by inspection: (3x - 2)(x - 3)

    by method:

    Step 1:
    take the first terms times the last term. we get 18x^2
    take the middle term, we have -11x

    Step 2:
    now think of two numbers that when multiplied gives 18x^2 and when added gives -11x

    the numbers are: -2x and -9x

    Step 3:
    rewrite the quadratic, this time writing the middle term in terms of these two numbers, we get:

    3x^2 - 9x - 2x + 6

    Step 4:
    factor by grouping:

    we have 3x common to the first two terms and -2 common to the last two, so we get:

    3x(x - 3) - 2(x - 3) ........factor out the common (x - 3)

    = (x - 3)(3x - 2)
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  3. #3
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    By inspection?

    May be this wretched Hint works

    11x=9x+2x
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  4. #4
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    Thanks for that help. Is there anyway you could show me the steps to that. I don't know how you got that. Sorry. If you can that would be wonderful but if not, the answer was enough help. Thanks again.

    Kasey
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  5. #5
    is up to his old tricks again! Jhevon's Avatar
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    Quote Originally Posted by flippin4u View Post
    Thanks for that help. Is there anyway you could show me the steps to that. I don't know how you got that. Sorry. If you can that would be wonderful but if not, the answer was enough help. Thanks again.

    Kasey
    when the coefficient of x^2 is small, like 2,3,4,5,6,7, or prime, you should be able to use inspection to figure the factors out, since there will not be many candidates for the first positions in the brackets. the method i gave you is for when you have larger numbers.
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