3x(x+4)=180

Solution for 3x(x+4)=180 equation:

3x(x+4)=180

We move all terms to the left:

3x(x+4)-(180)=0

We multiply parentheses

3x^2+12x-180=0

a = 3; b = 12; c = -180;
Δ = b2-4ac
Δ = 122-4·3·(-180)
Δ = 2304
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{2304}=48$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(12)-48}{2*3}=\frac{-60}{6}
=-10
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(12)+48}{2*3}=\frac{36}{6}
=6
$