How do you solve $-x^2 +2x +1 = 0$ using the quadratic formula?

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Answer 1 · 2016-05-24T10:30:04

$x={-sqrt2+1,sqrt2 +1}$

$-x^2+2x+1=0$

$ax^2+bx+c=0$

$Delta=sqrt(b^2-4*a*c)$

$x=(-b±Delta)/(2a)$

$a=-1$
$b=2$
$c=1$

$Delta=sqrt(2^2+4*1*1)$

$Delta=sqrt(4+4)$

$Delta=sqrt 8$

$Delta=2sqrt2$

$x_1=(-2-2sqrt2)/(2*(-1)$

$x_1=-2((1+sqrt2))/(-2)$

$x_1=1+sqrt2$

$x_2=(-2+2sqrt2)/(-2)$

$x_2=(-2(1-sqrt2))/(-2)$

$x_2=1-sqrt2$

How do you solve -x^2 +2x +1 = 0 -x^2 +2x +1 = 0 using the quadratic formula?