(3x-9)x+x(x+28)=184

Solution for (3x-9)x+x(x+28)=184 equation:

(3x-9)x+x(x+28)=184

We move all terms to the left:

(3x-9)x+x(x+28)-(184)=0

We multiply parentheses

3x^2+x^2-9x+28x-184=0

We add all the numbers together, and all the variables

4x^2+19x-184=0

a = 4; b = 19; c = -184;
Δ = b2-4ac
Δ = 192-4·4·(-184)
Δ = 3305
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{-(19)-\sqrt{3305}}{2*4}=\frac{-19-\sqrt{3305}}{8}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(19)+\sqrt{3305}}{2*4}=\frac{-19+\sqrt{3305}}{8}
$