X^2+2x=4.27

Solution for X^2+2x=4.27 equation:

X^2+2X=4.27

We move all terms to the left:

X^2+2X-(4.27)=0

We add all the numbers together, and all the variables

X^2+2X-4.27=0

a = 1; b = 2; c = -4.27;
Δ = b2-4ac
Δ = 22-4·1·(-4.27)
Δ = 21.08
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{-(2)-\sqrt{21.08}}{2*1}=\frac{-2-\sqrt{21.08}}{2}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(2)+\sqrt{21.08}}{2*1}=\frac{-2+\sqrt{21.08}}{2}
$