(6x+20)(2x)=180

Solution for (6x+20)(2x)=180 equation:

(6x+20)(2x)=180

We move all terms to the left:

(6x+20)(2x)-(180)=0

We multiply parentheses

12x^2+40x-180=0

a = 12; b = 40; c = -180;
Δ = b2-4ac
Δ = 402-4·12·(-180)
Δ = 10240
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:

$\sqrt{\Delta}=\sqrt{10240}=\sqrt{1024*10}=\sqrt{1024}*\sqrt{10}=32\sqrt{10}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(40)-32\sqrt{10}}{2*12}=\frac{-40-32\sqrt{10}}{24}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(40)+32\sqrt{10}}{2*12}=\frac{-40+32\sqrt{10}}{24}
$