18x^2-39+20=0

Solution for 18x^2-39+20=0 equation:

18x^2-39+20=0

We add all the numbers together, and all the variables

18x^2-19=0

a = 18; b = 0; c = -19;
Δ = b2-4ac
Δ = 02-4·18·(-19)
Δ = 1368
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:

$\sqrt{\Delta}=\sqrt{1368}=\sqrt{36*38}=\sqrt{36}*\sqrt{38}=6\sqrt{38}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-6\sqrt{38}}{2*18}=\frac{0-6\sqrt{38}}{36}
=-\frac{6\sqrt{38}}{36}
=-\frac{\sqrt{38}}{6}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+6\sqrt{38}}{2*18}=\frac{0+6\sqrt{38}}{36}
=\frac{6\sqrt{38}}{36}
=\frac{\sqrt{38}}{6}
$