x(x+4)-12=x=2

Solution for x(x+4)-12=x=2 equation:

x(x+4)-12=x=2

We move all terms to the left:

x(x+4)-12-(x)=0

We add all the numbers together, and all the variables

-1x+x(x+4)-12=0

We multiply parentheses

x^2-1x+4x-12=0

We add all the numbers together, and all the variables

x^2+3x-12=0

a = 1; b = 3; c = -12;
Δ = b2-4ac
Δ = 32-4·1·(-12)
Δ = 57
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(3)-\sqrt{57}}{2*1}=\frac{-3-\sqrt{57}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(3)+\sqrt{57}}{2*1}=\frac{-3+\sqrt{57}}{2}
$