54=(x+4)*x

Solution for 54=(x+4)*x equation:

54=(x+4)*x

We move all terms to the left:

54-((x+4)*x)=0


We calculate terms in parentheses: -((x+4)*x), so:

(x+4)*x

We multiply parentheses

x^2+4x

Back to the equation:

-(x^2+4x)


We get rid of parentheses

-x^2-4x+54=0

We add all the numbers together, and all the variables

-1x^2-4x+54=0

a = -1; b = -4; c = +54;
Δ = b2-4ac
Δ = -42-4·(-1)·54
Δ = 232
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:

$\sqrt{\Delta}=\sqrt{232}=\sqrt{4*58}=\sqrt{4}*\sqrt{58}=2\sqrt{58}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-4)-2\sqrt{58}}{2*-1}=\frac{4-2\sqrt{58}}{-2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-4)+2\sqrt{58}}{2*-1}=\frac{4+2\sqrt{58}}{-2}
$