-x^2-x=-30

Solution for -x^2-x=-30 equation:

-x^2-x=-30

We move all terms to the left:

-x^2-x-(-30)=0

We add all the numbers together, and all the variables

-1x^2-1x+30=0

a = -1; b = -1; c = +30;
Δ = b2-4ac
Δ = -12-4·(-1)·30
Δ = 121
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{121}=11$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-1)-11}{2*-1}=\frac{-10}{-2}
=+5
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-1)+11}{2*-1}=\frac{12}{-2}
=-6
$