20=x^2+6x+27

Solution for 20=x^2+6x+27 equation:

20=x^2+6x+27

We move all terms to the left:

20-(x^2+6x+27)=0

We get rid of parentheses

-x^2-6x-27+20=0

We add all the numbers together, and all the variables

-1x^2-6x-7=0

a = -1; b = -6; c = -7;
Δ = b2-4ac
Δ = -62-4·(-1)·(-7)
Δ = 8
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:

$\sqrt{\Delta}=\sqrt{8}=\sqrt{4*2}=\sqrt{4}*\sqrt{2}=2\sqrt{2}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-6)-2\sqrt{2}}{2*-1}=\frac{6-2\sqrt{2}}{-2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-6)+2\sqrt{2}}{2*-1}=\frac{6+2\sqrt{2}}{-2}
$