72=72x2

Solution for 72=72x2 equation:

72=72x^2

We move all terms to the left:

72-(72x^2)=0

a = -72; b = 0; c = +72;
Δ = b2-4ac
Δ = 02-4·(-72)·72
Δ = 20736
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{20736}=144$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-144}{2*-72}=\frac{-144}{-144}
=1
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+144}{2*-72}=\frac{144}{-144}
=-1
$