20x^2-36=0

Solution for 20x^2-36=0 equation:

20x^2-36=0

a = 20; b = 0; c = -36;
Δ = b2-4ac
Δ = 02-4·20·(-36)
Δ = 2880
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{2880}=\sqrt{576*5}=\sqrt{576}*\sqrt{5}=24\sqrt{5}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-24\sqrt{5}}{2*20}=\frac{0-24\sqrt{5}}{40}
=-\frac{24\sqrt{5}}{40}
=-\frac{3\sqrt{5}}{5}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+24\sqrt{5}}{2*20}=\frac{0+24\sqrt{5}}{40}
=\frac{24\sqrt{5}}{40}
=\frac{3\sqrt{5}}{5}
$