80x=4x*4x

Solution for 80x=4x*4x equation:

80x=4x*4x

We move all terms to the left:

80x-(4x*4x)=0

We add all the numbers together, and all the variables

80x-(+4x*4x)=0

We get rid of parentheses

80x-4x*4x=0

Wy multiply elements

-16x^2+80x=0

a = -16; b = 80; c = 0;
Δ = b2-4ac
Δ = 802-4·(-16)·0
Δ = 6400
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{6400}=80$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(80)-80}{2*-16}=\frac{-160}{-32}
=+5
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(80)+80}{2*-16}=\frac{0}{-32}
=0
$