x+20=x2+4x

Solution for x+20=x2+4x equation:

x+20=x2+4x

We move all terms to the left:

x+20-(x2+4x)=0

We add all the numbers together, and all the variables

-(+x^2+4x)+x+20=0

We get rid of parentheses

-x^2-4x+x+20=0

We add all the numbers together, and all the variables

-1x^2-3x+20=0

a = -1; b = -3; c = +20;
Δ = b2-4ac
Δ = -32-4·(-1)·20
Δ = 89
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{-(-3)-\sqrt{89}}{2*-1}=\frac{3-\sqrt{89}}{-2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-3)+\sqrt{89}}{2*-1}=\frac{3+\sqrt{89}}{-2}
$