How do you complete the square to solve $2 x^{2} + 9 x + 4 = 0$ $2x^2 + 9x + 4 = 0$ ?

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Answer 1 · 2015-05-31T19:05:26

a=2 b=9 c=4

$Delta=b²-4ac$
$Delta=9²-4*2*4$
$Delta=81-32$
$Delta=49$ ( =7² )

$x_1=(-b-sqrtDelta)/(2a)$

$x_1=(-9-7)/4$

$x_1=-16/4$

$x_1=-4$

$x_2=(-b+sqrtDelta)/(2a)$

$x_2=(-9+7)/4$

$x_2=-2/4$

$x_2=-1/2$

How do you complete the square to solve 2x^2 + 9x + 4 = 02x2+9x+4=02x^2 + 9x + 4 = 0?