36x(2x+1)=10800

Solution for 36x(2x+1)=10800 equation:

36x(2x+1)=10800

We move all terms to the left:

36x(2x+1)-(10800)=0

We multiply parentheses

72x^2+36x-10800=0

a = 72; b = 36; c = -10800;
Δ = b2-4ac
Δ = 362-4·72·(-10800)
Δ = 3111696
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{3111696}=1764$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(36)-1764}{2*72}=\frac{-1800}{144}
=-12+1/2
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(36)+1764}{2*72}=\frac{1728}{144}
=12
$