X(3x+40)=180

Solution for X(3x+40)=180 equation:

X(3X+40)=180

We move all terms to the left:

X(3X+40)-(180)=0

We multiply parentheses

3X^2+40X-180=0

a = 3; b = 40; c = -180;
Δ = b2-4ac
Δ = 402-4·3·(-180)
Δ = 3760
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:

$\sqrt{\Delta}=\sqrt{3760}=\sqrt{16*235}=\sqrt{16}*\sqrt{235}=4\sqrt{235}$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(40)-4\sqrt{235}}{2*3}=\frac{-40-4\sqrt{235}}{6}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(40)+4\sqrt{235}}{2*3}=\frac{-40+4\sqrt{235}}{6}
$