X2+12x=648

Solution for X2+12x=648 equation:

X2+12X=648

We move all terms to the left:

X2+12X-(648)=0

We add all the numbers together, and all the variables

X^2+12X-648=0

a = 1; b = 12; c = -648;
Δ = b2-4ac
Δ = 122-4·1·(-648)
Δ = 2736
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:

$\sqrt{\Delta}=\sqrt{2736}=\sqrt{144*19}=\sqrt{144}*\sqrt{19}=12\sqrt{19}$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(12)-12\sqrt{19}}{2*1}=\frac{-12-12\sqrt{19}}{2}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(12)+12\sqrt{19}}{2*1}=\frac{-12+12\sqrt{19}}{2}
$