1600=4x2

Solution for 1600=4x2 equation:

1600=4x^2

We move all terms to the left:

1600-(4x^2)=0

a = -4; b = 0; c = +1600;
Δ = b2-4ac
Δ = 02-4·(-4)·1600
Δ = 25600
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{25600}=160$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-160}{2*-4}=\frac{-160}{-8}
=+20
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+160}{2*-4}=\frac{160}{-8}
=-20
$