(0.15+x)(x+0.05)=1

Solution for (0.15+x)(x+0.05)=1 equation:

(0.15+x)(x+0.05)=1

We move all terms to the left:

(0.15+x)(x+0.05)-(1)=0

We add all the numbers together, and all the variables

(x+0.15)(x+0.05)-1=0

We multiply parentheses ..

(+x^2+0.05x+0.15x+0.0075)-1=0

We get rid of parentheses

x^2+0.05x+0.15x+0.0075-1=0

We add all the numbers together, and all the variables

x^2+0.2x-0.9925=0

a = 1; b = 0.2; c = -0.9925;
Δ = b2-4ac
Δ = 0.22-4·1·(-0.9925)
Δ = 4.01
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{-(0.2)-\sqrt{4.01}}{2*1}=\frac{-0.2-\sqrt{4.01}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0.2)+\sqrt{4.01}}{2*1}=\frac{-0.2+\sqrt{4.01}}{2}
$