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# maths quick question help!!! asap watch

1. 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
2. (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.
3. 4x2 - x - 8 = 0

you want to get

a(x - b)2 - c = 0

so expand ^ then compare to find a,b,c
4. (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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Updated: September 11, 2015
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