-x2-30x+5400=0

Solution for -x2-30x+5400=0 equation:

-x2-30x+5400=0

We add all the numbers together, and all the variables

-1x^2-30x+5400=0

a = -1; b = -30; c = +5400;
Δ = b2-4ac
Δ = -302-4·(-1)·5400
Δ = 22500
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{22500}=150$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-30)-150}{2*-1}=\frac{-120}{-2}
=+60
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-30)+150}{2*-1}=\frac{180}{-2}
=-90
$