-3x(x-10)+5=-4

Solution for -3x(x-10)+5=-4 equation:

-3x(x-10)+5=-4

We move all terms to the left:

-3x(x-10)+5-(-4)=0

We add all the numbers together, and all the variables

-3x(x-10)+9=0

We multiply parentheses

-3x^2+30x+9=0

a = -3; b = 30; c = +9;
Δ = b2-4ac
Δ = 302-4·(-3)·9
Δ = 1008
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{1008}=\sqrt{144*7}=\sqrt{144}*\sqrt{7}=12\sqrt{7}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(30)-12\sqrt{7}}{2*-3}=\frac{-30-12\sqrt{7}}{-6}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(30)+12\sqrt{7}}{2*-3}=\frac{-30+12\sqrt{7}}{-6}
$