x+(2x-10)+x(x+10)=180

Solution for x+(2x-10)+x(x+10)=180 equation:

x+(2x-10)+x(x+10)=180

We move all terms to the left:

x+(2x-10)+x(x+10)-(180)=0

We multiply parentheses

x^2+x+(2x-10)+10x-180=0

We get rid of parentheses

x^2+x+2x+10x-10-180=0

We add all the numbers together, and all the variables

x^2+13x-190=0

a = 1; b = 13; c = -190;
Δ = b2-4ac
Δ = 132-4·1·(-190)
Δ = 929
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(13)-\sqrt{929}}{2*1}=\frac{-13-\sqrt{929}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(13)+\sqrt{929}}{2*1}=\frac{-13+\sqrt{929}}{2}
$