.(2x-1)+(5x+11)=180

Solution for .(2x-1)+(5x+11)=180 equation:

.(2x-1)+(5x+11)=180

We move all terms to the left:

.(2x-1)+(5x+11)-(180)=0

We multiply parentheses

2x^2+(5x+11)-180+=0

We get rid of parentheses

2x^2+5x+11-180+=0

We add all the numbers together, and all the variables

2x^2+5x=0

a = 2; b = 5; c = 0;
Δ = b2-4ac
Δ = 52-4·2·0
Δ = 25
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{25}=5$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(5)-5}{2*2}=\frac{-10}{4}
=-2+1/2
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(5)+5}{2*2}=\frac{0}{4}
=0
$