A=-4w^2+64w

Solution for A=-4w^2+64w equation:

=-4A^2+64A

We move all terms to the left:

-(-4A^2+64A)=0

We get rid of parentheses

4A^2-64A=0

a = 4; b = -64; c = 0;
Δ = b2-4ac
Δ = -642-4·4·0
Δ = 4096
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$A_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$A_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{4096}=64$
$A_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-64)-64}{2*4}=\frac{0}{8}
=0
$
$A_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-64)+64}{2*4}=\frac{128}{8}
=16
$