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    Basically the question is
    Two lines have equations
    Y=root2 x+9
    y=10-x
    I know you do root2 x+9=10-x,
    Then you get root2+2x=1
    2x=1-root2
    And i get x=1-root2/2
    The answer should just be x=1-root2
    Where did igo wrong?
    Thanks
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    I think the answer is actually x=\sqrt{2}-1.

    I'm not going to show you all the steps, but the first few so you can see where you've gone wrong:

    10-x = \sqrt{2} x+9
    1 = x + \sqrt{2} x
    1 = x(1+\sqrt{2})
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    (Original post by ViralRiver)
    I think the answer is actually x=\sqrt{2}-1.

    I'm not going to show you all the steps, but the first few so you can see where you've gone wrong:

    10-x = \sqrt{2} x+9
    1 = x + \sqrt{2} x
    1 = x(1+\sqrt{2})
    After that would you do x-1=root2+1?
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    (Original post by mamma_mia123)
    After that would you do x-1=root2+1?
    no

    the x is times the bracket so you need to divide
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    (Original post by TenOfThem)
    no

    the x is times the bracket so you need to divide
    So its 1/x=root2+1
    then what?
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    Since you want x on its own you would divide by the bracket so that you have x =

    Then you need to rationalise the denominator
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    (Original post by TenOfThem)
    Since you want x on its own you would divide by the bracket so that you have x =

    Then you need to rationalise the denominator
    Thanks, i actually forgot whqt i was trying to find btw, i you had 4root6pi/4, could you cancel down to root6pii (pi root 6)?
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    (Original post by mamma_mia123)
    Thanks, i actually forgot whqt i was trying to find btw, i you had 4root6pi/4, could you cancel down to root6pii (pi root 6)?
    If you're asking whether \frac{4\pi\sqrt{6}}{4} = \pi\sqrt{6}, then yes it does.
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    (Original post by ViralRiver)
    If you're asking whether \frac{4\pi\sqrt{6}}{4} = \pi\sqrt{6}, then yes it does.
    Hello, would 1/4 x2 multiplied by x2=1/4 x4?
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    (Original post by mamma_mia123)
    Hello, would 1/4 x2 multiplied by x2=1/4 x4?
    Not sure what you're asking, unless you mean \frac{1}{4}\times 2\times 2=\frac{1}{4} \times 4=\frac{4}{4}=1, in which case you're right .
 
 
 
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