x^2-9x*81=0

Solution for x^2-9x*81=0 equation:

x^2-9x*81=0

Wy multiply elements

x^2-729x=0

a = 1; b = -729; c = 0;
Δ = b2-4ac
Δ = -7292-4·1·0
Δ = 531441
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{531441}=729$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-729)-729}{2*1}=\frac{0}{2}
=0
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-729)+729}{2*1}=\frac{1458}{2}
=729
$