-3x^2-66x+8=0

Solution for -3x^2-66x+8=0 equation:

-3x^2-66x+8=0

a = -3; b = -66; c = +8;
Δ = b2-4ac
Δ = -662-4·(-3)·8
Δ = 4452
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{4452}=\sqrt{4*1113}=\sqrt{4}*\sqrt{1113}=2\sqrt{1113}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-66)-2\sqrt{1113}}{2*-3}=\frac{66-2\sqrt{1113}}{-6}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-66)+2\sqrt{1113}}{2*-3}=\frac{66+2\sqrt{1113}}{-6}
$