3x(x-28)=180

Solution for 3x(x-28)=180 equation:

3x(x-28)=180

We move all terms to the left:

3x(x-28)-(180)=0

We multiply parentheses

3x^2-84x-180=0

a = 3; b = -84; c = -180;
Δ = b2-4ac
Δ = -842-4·3·(-180)
Δ = 9216
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{9216}=96$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-84)-96}{2*3}=\frac{-12}{6}
=-2
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-84)+96}{2*3}=\frac{180}{6}
=30
$