How do you solve $x^2 + 7x – 1 = 0$ ?

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Answer 1 · 2015-09-11T12:56:23

The solutions are
$color(blue)(x= (-7+sqrt(53))/2$
$color(blue)(x= (-7-sqrt(53))/2$

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

$a=1, b= 7, c= -1$

The Discriminant is given by:
$Delta=b^2-4*a*c$
$= (7)^2-(4*(1)* -1)$
$= 49 +4 = 53$

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

$x = (-7+-sqrt(53))/(2*1) = (-7+-sqrt(53))/2$

The solutions are
$color(blue)(x= (-7+sqrt(53))/2$
$color(blue)(x= (-7-sqrt(53))/2$

How do you solve x^2 + 7x – 1 = 0x^2 + 7x – 1 = 0?