How do you solve $-2x^2 + 5x + 1/8$ by completing the square?

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Answer 1 · 2015-05-01T03:00:46

Change side and divide by a:

$f(x) = x^2 - 5/2 x - 1/16 = 0$

$f(x) = x^2 - 5/2 x + 25/16 - 25/16 - 1/16 = 0$

$( x - 5/4)^2 = 25/16 + 1/16 = 26/16$

$(x - 5/4) = (sqr26)/4 --> x = 5/4 + (sqr26)/4$

$(x - 5/4) = (-sqr26)/4 --> x = 5/4 - (sqr26)/4$

How do you solve -2x^2 + 5x + 1/8 -2x^2 + 5x + 1/8 by completing the square?