39*39=x*x+6x+12

Solution for 39*39=x*x+6x+12 equation:

39*39=x*x+6x+12

We move all terms to the left:

39*39-(x*x+6x+12)=0

We add all the numbers together, and all the variables

-(6x+x*x+12)+39*39=0

We add all the numbers together, and all the variables

-(6x+x*x+12)+1521=0

We get rid of parentheses

-6x-x*x-12+1521=0

We add all the numbers together, and all the variables

-6x-x*x+1509=0

Wy multiply elements

-1x^2-6x+1509=0

a = -1; b = -6; c = +1509;
Δ = b2-4ac
Δ = -62-4·(-1)·1509
Δ = 6072
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:

$\sqrt{\Delta}=\sqrt{6072}=\sqrt{4*1518}=\sqrt{4}*\sqrt{1518}=2\sqrt{1518}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-6)-2\sqrt{1518}}{2*-1}=\frac{6-2\sqrt{1518}}{-2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-6)+2\sqrt{1518}}{2*-1}=\frac{6+2\sqrt{1518}}{-2}
$