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Math Help - Solving for x

  1. #1
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    Solving for x

    How do I find x for

    1 = x(x-6)
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  2. #2
    Super Member Quacky's Avatar
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    x(x-6)=1
    Expand the brackets by multiplying everything inside the bracket with everything outside the bracket term by term to obtain:

    x^2-6x=1 Then rearrange:

    x^2-6x-1=0

    Which is just a standard solvable quadratic, but it won't factorize, so you'll either have to use the formula or complete the square. Can you remember how to do that?
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  3. #3
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    Yeh. Plug in the values and you get x= 6.1623 and x= -0.16228

    And if you were to solve for 1 = (x-3)(x+1)

    you just expand, set the equation to 0 and find the x's right?
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  4. #4
    Super Member Quacky's Avatar
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    Quote Originally Posted by Devi09 View Post
    Yeh. Plug in the values and you get x= 6.1623 and x= -0.16228

    And if you were to solve for 1 = (x-3)(x+1)

    you just expand and find the x's right?
    Yeah, it's a similar approach.
    x^2-3x+1x-3=1

    x^2-2x-4=0

    etc...
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  5. #5
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    Quote Originally Posted by Devi09 View Post
    Yeh. Plug in the values and you get x= 6.1623 and x= -0.16228
    Note exactly, keep your answer in its surd form...

    And if you were to solve for 1 = (x-3)(x+1)

    you just expand, set the equation to 0 and find the x's right?
    Yes, again if you have surd values, keep them as surds.
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