Solve using the Quadratic Formula:?

x = [-b ± √(b² - 4ac)] / (2a)
x = [ -(6) ± √(6² - 4(1)(-3)] / (2(1))
x = [ -6 ± √(36 + 12)] / 2
x = [ -6 ± √(48)] / 2
x = [ -6 ± √(16 * 3)] / 2
x = [ -6 ± 4√(3)] / 2
x = -3 ± 2√3

You have to foil it.

but this one has lotsa decimals.

but like
x^2+6x+5=0
(x+3)(x+2)
x+3=0
x+2=0
so x = -2 or -3

x^2 + 6x - 3 = 0
x = [-b ±√(b^2 - 4ac)]/2a

a = 1
b = 6
c = -3

x = [-6 ±√(36 + 12)]/2
x = [-6 ±√48]/2
x = [-6 ±6.92]/2 (approx.)

x = [-6 + 6.92]/2
x = 0.92/2
x = 0.46

x = [-6 - 6.92]/2
x = -12.92/2
x = -6.46

∴ x = -6.46 , 0.46

Ax^2 + Bx + C

-B +/- (B^2 - 4AC)^0.5 all divided by 2A

-3 +/- sqroot(6) will give you the two roots

x1,2=-6+-sqrt(36+12)/2=-6+-4sqrt(3)/2=-3+-2sqrt(3)

Quadratic Formula:

-b +/- sqrt(b² - 4ac)
----------------------------
2a

So...

-6 +/- sqrt(36 - 4(1)(-3))
---------------------------------
2

-3 +/- sqrt(36 + 12) / 2

-3 +/- sqrt(48) / 2

-3 +/- 4 * sqrt(3) / 2

-3 +/- (2 * sqrt(3))

x = -3 + (2 * sqrt(3))
and
x = -3 - (2 * sqrt(3))

0.46410
-6.4641

See http://www.mathwarehouse.com/quadratic/quadratic-formula-calculator.php