(x+11)(x+3)=425

Solution for (x+11)(x+3)=425 equation:

(x+11)(x+3)=425

We move all terms to the left:

(x+11)(x+3)-(425)=0

We multiply parentheses ..

(+x^2+3x+11x+33)-425=0

We get rid of parentheses

x^2+3x+11x+33-425=0

We add all the numbers together, and all the variables

x^2+14x-392=0

a = 1; b = 14; c = -392;
Δ = b2-4ac
Δ = 142-4·1·(-392)
Δ = 1764
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1764}=42$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(14)-42}{2*1}=\frac{-56}{2}
=-28
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(14)+42}{2*1}=\frac{28}{2}
=14
$