SOLUTION: Find the positive roots of the equation 4x squared +27x=40 by completing the square

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Question 384467: Find the positive roots of the equation 4x squared +27x=40 by completing the square
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Find the positive roots of the equation 4x squared +27x=40 by completing the square
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4x^2 + 27x = 40
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4(x^2+(27/4)x + (27/8)^2) = 40+ 4(27/8)^2
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4(x+(27/8))^2 = 85.5625
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(x+(27/8)) = +/-sqrt[85.5625/4]
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x+(27/8) = +/-4.625
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x = -(27/8)+-4.625
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x = 1.25 and x = -8
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Cheers,
Stan H.