(10x+18)(3x+6)=180

Solution for (10x+18)(3x+6)=180 equation:

(10x+18)(3x+6)=180

We move all terms to the left:

(10x+18)(3x+6)-(180)=0

We multiply parentheses ..

(+30x^2+60x+54x+108)-180=0

We get rid of parentheses

30x^2+60x+54x+108-180=0

We add all the numbers together, and all the variables

30x^2+114x-72=0

a = 30; b = 114; c = -72;
Δ = b2-4ac
Δ = 1142-4·30·(-72)
Δ = 21636
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:

$\sqrt{\Delta}=\sqrt{21636}=\sqrt{36*601}=\sqrt{36}*\sqrt{601}=6\sqrt{601}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(114)-6\sqrt{601}}{2*30}=\frac{-114-6\sqrt{601}}{60}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(114)+6\sqrt{601}}{2*30}=\frac{-114+6\sqrt{601}}{60}
$