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maths quick question help!!! asap watch

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    hi can anyone show me a step by step answer for this problem, i just dont understand it ::
    solve this by completing the square........ 4x^2-x=8
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    (Original post by papajani1234)
    hi can anyone show me a step by step answer for this problem, i just dont understand it ::
    solve this by completing the square........ 4x^2-x=8
    Rearrange to get in the form ax2 + bx + c = 0. You can then divide through by a and use the completing the square method to solve.
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    4x2 - x - 8 = 0

    you want to get

    a(x - b)2 - c = 0

    so expand ^ then compare to find a,b,c
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    (Original post by papajani1234)
    hi can anyone show me a step by step answer for this problem, i just dont understand it ::
    solve this by completing the square........ 4x^2-x=8
    4x^2-x-8=0
    4(x^2-x/4-2)=0
    4((x-1/8)^2 -1/64-2)=0
    4((x-1/8)^2 -129/64)=0
    4(x-1/8)^2 -129/16=0
    4(x-1/8)^2= 129/16
    (x-1/8)^2 =129/64
    x-1/8 = +/- SQRT(129)/8
    x = 1/8 +/- SQRT(129)/8
 
 
 
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