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Math Help - equation

  1. #1
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    equation

    i've got to factorise 6x^2 + 5x - 6 and i've used the steps i've been shown so far to get to this: multiply 6 and -6 to get -36. find two numbers that add together to make 5 and multiply to make -36. i came to -4 and 9. i put them into the middle of the equation while removing the 5x as instructed so i came to 6x^2 -4x + 9x - 6 grouped them and then factored them x(6x - 4)   3(3x-2). just wondering where i go from here. any detailed steps would be appreciated
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  2. #2
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    you're almost there
    x(6x - 4)+3(3x-2) = 2x(3x-2)+3(3x-2)= (2x+3)(3x-2)

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  3. #3
    Member Mauritzvdworm's Avatar
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    i've got to factorise
    6x^{2}+5x-6=(2x+3)(3x-2)

    just play around with the integers that make up 6 namely 1,2,3 and 6. We see that the final term has a minus sign attached to it so we know we need to incorporate that

    3\times 3x-2x\times 2=9x-4x=5x
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  4. #4
    DBA
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    If you have x(6x - 4) 3(3x-2) --> you forgot the plus sign here,
    the next step would be 2x(3x-2)+3(3x-2). Both factors need to be the same.
    For (6x-4) you can write 2(3x-2)

    Now, if you have 2x(3x-2)+3(3x-2), you can factor to (2x+3)(3x-2), which is 6x^2+5x-6
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  5. #5
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    anyone have any info on what to do when there is no constant and only 2 numbers? ie how would i go about 5x-2x^2? thanks
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  6. #6
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    Then x(5-2x) is the factorization, it's that simple.
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