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Math Help - Fatoring polinomials - what am I doing wrong?

  1. #1
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    Fatoring polinomials - what am I doing wrong?

    Hi! Here is the problem I was trying to solve, and what I did:

    3x^2+7x-6=0
    Since 3*(-6)=-18, I need two numbrers, the product of which is -18, and the sum of which is 7. I chose -9 and 2.
    3x^2-9x+2x-6=0
    3x(x-3)+2(x-3)=0
    (3x+2)(x-3)=0
    3x+2=0 or x-3=0
    x=3 x=-2/3


    However, the back of the textbook gives the answer x=-3 x=2/3
    What is wrong? Thanks if you could help, big time! I didn't do grade 10 math, and in grade 11 they only review factoring for a couple of lessons.
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  2. #2
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    double post, mod pls delete...
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