x(1/5)=10800-x

Solution for x(1/5)=10800-x equation:

x(1/5)=10800-x

We move all terms to the left:

x(1/5)-(10800-x)=0

We add all the numbers together, and all the variables

x(+1/5)-(-1x+10800)=0

We multiply parentheses

x^2-(-1x+10800)=0

We get rid of parentheses

x^2+1x-10800=0

We add all the numbers together, and all the variables

x^2+x-10800=0

a = 1; b = 1; c = -10800;
Δ = b2-4ac
Δ = 12-4·1·(-10800)
Δ = 43201
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(1)-\sqrt{43201}}{2*1}=\frac{-1-\sqrt{43201}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(1)+\sqrt{43201}}{2*1}=\frac{-1+\sqrt{43201}}{2}
$