3x^2+12x+9=143^2

Solution for 3x^2+12x+9=143^2 equation:

3x^2+12x+9=143^2

We move all terms to the left:

3x^2+12x+9-(143^2)=0

We add all the numbers together, and all the variables

3x^2+12x-20440=0

a = 3; b = 12; c = -20440;
Δ = b2-4ac
Δ = 122-4·3·(-20440)
Δ = 245424
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:

$\sqrt{\Delta}=\sqrt{245424}=\sqrt{16*15339}=\sqrt{16}*\sqrt{15339}=4\sqrt{15339}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(12)-4\sqrt{15339}}{2*3}=\frac{-12-4\sqrt{15339}}{6}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(12)+4\sqrt{15339}}{2*3}=\frac{-12+4\sqrt{15339}}{6}
$