-y^2-12y-16=0

Solution for -y^2-12y-16=0 equation:

-y^2-12y-16=0

We add all the numbers together, and all the variables

-1y^2-12y-16=0

a = -1; b = -12; c = -16;
Δ = b2-4ac
Δ = -122-4·(-1)·(-16)
Δ = 80
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{80}=\sqrt{16*5}=\sqrt{16}*\sqrt{5}=4\sqrt{5}$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-12)-4\sqrt{5}}{2*-1}=\frac{12-4\sqrt{5}}{-2}
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-12)+4\sqrt{5}}{2*-1}=\frac{12+4\sqrt{5}}{-2}
$