x2+5x=11

Solution for x2+5x=11 equation:

x2+5x=11

We move all terms to the left:

x2+5x-(11)=0

We add all the numbers together, and all the variables

x^2+5x-11=0

a = 1; b = 5; c = -11;
Δ = b2-4ac
Δ = 52-4·1·(-11)
Δ = 69
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{-(5)-\sqrt{69}}{2*1}=\frac{-5-\sqrt{69}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(5)+\sqrt{69}}{2*1}=\frac{-5+\sqrt{69}}{2}
$