(x+0.2)(x+0.2)=0.489897949

Solution for (x+0.2)(x+0.2)=0.489897949 equation:

(x+0.2)(x+0.2)=0.489897949

We move all terms to the left:

(x+0.2)(x+0.2)-(0.489897949)=0

We add all the numbers together, and all the variables

(x+0.2)(x+0.2)-0.489897949=0

We multiply parentheses ..

(+x^2+0.2x+0.2x+0.04)-0.489897949=0

We get rid of parentheses

x^2+0.2x+0.2x+0.04-0.489897949=0

We add all the numbers together, and all the variables

x^2+0.4x-0.449897949=0

a = 1; b = 0.4; c = -0.449897949;
Δ = b2-4ac
Δ = 0.42-4·1·(-0.449897949)
Δ = 1.959591796
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{-(0.4)-\sqrt{1.959591796}}{2*1}=\frac{-0.4-\sqrt{1.959591796}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0.4)+\sqrt{1.959591796}}{2*1}=\frac{-0.4+\sqrt{1.959591796}}{2}
$