How do you solve $5x^2 + 8x + 7 = 0$ using the quadratic formula?

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Answer 1 · 2015-10-21T04:45:23

The solutions are
$x=color(blue)((-8+sqrt(-76))/10$
$x=color(blue)((-8-sqrt(-76))/10$

$5x^2+8x+7=0$

The equation is of the form $color(blue)(ax^2+bx+c=0$ where:
$a=5, b=8, c=7$

The Discriminant is given by:

$Delta=b^2-4*a*c$

$= (8)^2-(4*5*7)$

$= 64- 140= -76$

The solutions are normally found using the formula
$x=(-b+-sqrtDelta)/(2*a)$

$x = (-(8)+-sqrt(-76))/(2*5) = (-8+-sqrt(-76))/10$

The solutions are
$x=color(blue)((-8+sqrt(-76))/10$
$x=color(blue)((-8-sqrt(-76))/10$

How do you solve 5x^2 + 8x + 7 = 0 5x^2 + 8x + 7 = 0 using the quadratic formula?