(0.70-x)(0.045-x)=0

Solution for (0.70-x)(0.045-x)=0 equation:

(0.70-x)(0.045-x)=0

We add all the numbers together, and all the variables

(-1x+0.7)(-1x+0.045)=0

We multiply parentheses ..

(+x^2-0.045x-0.7x+0.0315)=0

We get rid of parentheses

x^2-0.045x-0.7x+0.0315=0

We add all the numbers together, and all the variables

x^2-0.745x+0.0315=0

a = 1; b = -0.745; c = +0.0315;
Δ = b2-4ac
Δ = -0.7452-4·1·0.0315
Δ = 0.429025
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{-(-0.745)-\sqrt{0.429025}}{2*1}=\frac{0.745-\sqrt{0.429025}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-0.745)+\sqrt{0.429025}}{2*1}=\frac{0.745+\sqrt{0.429025}}{2}
$