How do you solve $2x² + 8x + 5 = 0$ by completing the square?

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Answer 1 · 2017-07-21T14:30:11

$x = -2 +- sqrt3/sqrt2$

$2x^2 + 8x = - 5$
Divide both sides by 2
$x^2 + 4x = - 5/2$
$x^2 + 4x + 4 = 4 - 5/2 = 3/2$ .
$(x + 2)^2 = 3/2$
$x + 2 = +- sqrt3/sqrt2$ .

$x = - 2 +- sqrt3/sqrt2$ .

How do you solve 2x² + 8x + 5 = 02x² + 8x + 5 = 0 by completing the square?