(0.2-x)(0.25-x)=0.01

Solution for (0.2-x)(0.25-x)=0.01 equation:

(0.2-x)(0.25-x)=0.01

We move all terms to the left:

(0.2-x)(0.25-x)-(0.01)=0

We add all the numbers together, and all the variables

(-1x+0.2)(-1x+0.25)-(0.01)=0

We add all the numbers together, and all the variables

(-1x+0.2)(-1x+0.25)-0.01=0

We multiply parentheses ..

(+x^2-0.25x-0.2x+0.05)-0.01=0

We get rid of parentheses

x^2-0.25x-0.2x+0.05-0.01=0

We add all the numbers together, and all the variables

x^2-0.45x+0.04=0

a = 1; b = -0.45; c = +0.04;
Δ = b2-4ac
Δ = -0.452-4·1·0.04
Δ = 0.0425
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{-(-0.45)-\sqrt{0.0425}}{2*1}=\frac{0.45-\sqrt{0.0425}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-0.45)+\sqrt{0.0425}}{2*1}=\frac{0.45+\sqrt{0.0425}}{2}
$