12/x=x-4

Solution for 12/x=x-4 equation:

12/x=x-4

We move all terms to the left:

12/x-(x-4)=0


Domain of the equation: x!=0

x∈R


We get rid of parentheses

12/x-x+4=0

We multiply all the terms by the denominator


-x*x+4*x+12=0

We add all the numbers together, and all the variables

4x-x*x+12=0

Wy multiply elements

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

a = -1; b = 4; c = +12;
Δ = b2-4ac
Δ = 42-4·(-1)·12
Δ = 64
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{64}=8$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(4)-8}{2*-1}=\frac{-12}{-2}
=+6
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(4)+8}{2*-1}=\frac{4}{-2}
=-2
$