20x^2-100x=-120

Solution for 20x^2-100x=-120 equation:

20x^2-100x=-120

We move all terms to the left:

20x^2-100x-(-120)=0

We add all the numbers together, and all the variables

20x^2-100x+120=0

a = 20; b = -100; c = +120;
Δ = b2-4ac
Δ = -1002-4·20·120
Δ = 400
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{400}=20$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-100)-20}{2*20}=\frac{80}{40}
=2
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-100)+20}{2*20}=\frac{120}{40}
=3
$