What are the zero(s) of: x^2 = 6x + 6 = 0?

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Answer 1 · 2015-11-09T22:09:14

$3+ sqrt(15) , 3- sqrt(15)$

We can use the quadratic formula to find the zeros. We are given:

$x^2=6x+6$

We can arrange this into a quadratic equation:

$x^2-6x-6=0$

The quadratic formula:

$x=(-b(+/-) sqrt(b^2-4ac))/(2a)$

If:
$a=1, b=-6, c=-6$
Then:

$x=(-(-6)(+/-) sqrt((-6)^2-4(1)(-6)))/(2(1))= (6(+/-) sqrt(36+24))/2$
$x=(6(+/-)sqrt(60))/2=(6(+/-) 2sqrt(15))/2= 3(+/-) sqrt(15)$