(X+8)(3x)=180

Solution for (X+8)(3x)=180 equation:

(X+8)(3X)=180

We move all terms to the left:

(X+8)(3X)-(180)=0

We multiply parentheses

3X^2+24X-180=0

a = 3; b = 24; c = -180;
Δ = b2-4ac
Δ = 242-4·3·(-180)
Δ = 2736
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:

$\sqrt{\Delta}=\sqrt{2736}=\sqrt{144*19}=\sqrt{144}*\sqrt{19}=12\sqrt{19}$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(24)-12\sqrt{19}}{2*3}=\frac{-24-12\sqrt{19}}{6}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(24)+12\sqrt{19}}{2*3}=\frac{-24+12\sqrt{19}}{6}
$