90-50(40)4x2=80

Solution for 90-50(40)4x2=80 equation:

90-50(40)4x^2=80

We move all terms to the left:

90-50(40)4x^2-(80)=0

We add all the numbers together, and all the variables

-50404x^2+10=0

a = -50404; b = 0; c = +10;
Δ = b2-4ac
Δ = 02-4·(-50404)·10
Δ = 2016160
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:

$\sqrt{\Delta}=\sqrt{2016160}=\sqrt{16*126010}=\sqrt{16}*\sqrt{126010}=4\sqrt{126010}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-4\sqrt{126010}}{2*-50404}=\frac{0-4\sqrt{126010}}{-100808}
=-\frac{4\sqrt{126010}}{-100808}
=-\frac{\sqrt{126010}}{-25202}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+4\sqrt{126010}}{2*-50404}=\frac{0+4\sqrt{126010}}{-100808}
=\frac{4\sqrt{126010}}{-100808}
=\frac{\sqrt{126010}}{-25202}
$