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algebra

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-12x+10/5 = - x/20
I can't decide if I should cross multiply by -20 or just 20. The - is in the middle of the x and 20 (like a fraction)
I came up with 2 possible answers:
x=40/49 and x = 40/47

  • algebra -

    I am not a big fan of the expression "cross multiply"
    What you want to do here is multiply both sides, all terms by -20 (or 20 would work too)
    FIRST THE WAY YOU TYPED IT (probably wrong)
    -12(-20) x + 2(-20 ) = -x(-20)
    240 x - 40 = 20 x
    220 x = 40
    x = 2/11
    NOW WHAT I THINK YOU MEAN
    (-12x+10)(-20)/5 = -x (-20/20)
    48 x -40 = -x
    49 x = 40
    x = 40/49
    PARENTHESES ARE IMPORTANT WHEN TYPING EQUATION ON A COMPUTER (because of order of operations)

  • typo -

    (-12x+10)(-20)/5 = -x (-20/20)
    I made a sign error here
    48 x -40 = +x
    47 x = 40
    x = 40/47

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