-3y^2-16y+75=0

Solution for -3y^2-16y+75=0 equation:

-3y^2-16y+75=0

a = -3; b = -16; c = +75;
Δ = b2-4ac
Δ = -162-4·(-3)·75
Δ = 1156
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1156}=34$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-16)-34}{2*-3}=\frac{-18}{-6}
=+3
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-16)+34}{2*-3}=\frac{50}{-6}
=-8+1/3
$