(X+4)(9x)=108

Solution for (X+4)(9x)=108 equation:

(X+4)(9X)=108

We move all terms to the left:

(X+4)(9X)-(108)=0

We multiply parentheses

9X^2+36X-108=0

a = 9; b = 36; c = -108;
Δ = b2-4ac
Δ = 362-4·9·(-108)
Δ = 5184
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{5184}=72$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(36)-72}{2*9}=\frac{-108}{18}
=-6
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(36)+72}{2*9}=\frac{36}{18}
=2
$