-3s^2+3s-1=-91

Solution for -3s^2+3s-1=-91 equation:

-3s^2+3s-1=-91

We move all terms to the left:

-3s^2+3s-1-(-91)=0

We add all the numbers together, and all the variables

-3s^2+3s+90=0

a = -3; b = 3; c = +90;
Δ = b2-4ac
Δ = 32-4·(-3)·90
Δ = 1089
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$s_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$s_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1089}=33$
$s_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(3)-33}{2*-3}=\frac{-36}{-6}
=+6
$
$s_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(3)+33}{2*-3}=\frac{30}{-6}
=-5
$