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    • Thread Starter
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    Find, as surds, the roots of the equation:

    2(x+1)(x-4) -(x-2)^2 = 0

    I'm not sure of the method.
    Please explain your steps if you answe rit.
    • PS Reviewer
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    Have you tried expanding the brackets to result in a nicer equation?
    • Thread Starter
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    (Original post by Slowbro93)
    Have you tried expanding the brackets to result in a nicer equation?
    Yes.
    • PS Reviewer
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    (Original post by oneabdi)
    Yes.
    So what is the quadratic you now have?
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    (Original post by oneabdi)
    Yes.
    Then solve the resulting quadratic using either completing the square or the quadratic formula but don't use your calculator and leave your answers as surd solutions


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    Expand the brackets and simplify. Complete the square or use the quadratic formula to find the roots.


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    (Original post by oneabdi)
    Find, as surds, the roots of the equation:

    2(x+1)(x-4) -(x-2)^2 = 0

    I'm not sure of the method.
    Please explain your steps if you answe rit.
    Right, I tied doing it like this but I’m not sure whether itis correct:
    2(x+1)(x-4)-(x-2)(x-2)=0
    2(x^2-3x-4)-(x^2-4x+4)=0
    2x^2-6x-8-x^2+4x-4=0
    X^2-2x-12=0
    Complete the square:
    (x-1)^2-(1)^2=12
    (x-1)^2=13
    X-1=square root 13
    X=1+square root 13 or x= 1-square root 13
    • Study Helper
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    (Original post by lewisthornton)
    2(x+1)(x-4) -(x-2)^2 = 0

    (Original post by 08rgill)
    ...
    Please don't post full solutions - it's against forum rules
 
 
 
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