How do you solve $x² -3x-7=0$ ?

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Answer 1 · 2015-08-20T13:00:15

The solutions are
$color(blue)(x=(3+sqrt(37))/2$

$color(blue)(x=(3-sqrt(37))/2$

$x^2-3x-7=0$

The equation is of the form $color(blue)(ax^2+bx+c=0$ where:
$a=1, b=-3, c=-7$

The Discriminant is given by:
$Delta=b^2-4*a*c$
$= (-3)^2-(4*1*-7)$
$= 9+28=37$

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

$x = (-(-3)+-sqrt(37))/(2*1) = (3+-sqrt(37))/2$

The solutions are
$color(blue)(x=(3+sqrt(37))/2$

$color(blue)(x=(3-sqrt(37))/2$

How do you solve x² -3x-7=0x² -3x-7=0?