(1.6-x)(5.6-x)=0

Solution for (1.6-x)(5.6-x)=0 equation:

(1.6-x)(5.6-x)=0

We add all the numbers together, and all the variables

(-1x+1.6)(-1x+5.6)=0

We multiply parentheses ..

(+x^2-5.6x-1.6x+8.96)=0

We get rid of parentheses

x^2-5.6x-1.6x+8.96=0

We add all the numbers together, and all the variables

x^2-7.2x+8.96=0

a = 1; b = -7.2; c = +8.96;
Δ = b2-4ac
Δ = -7.22-4·1·8.96
Δ = 16
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{16}=4$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-7.2)-4}{2*1}=\frac{3.2}{2}
=1+1/1.6666666666667
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-7.2)+4}{2*1}=\frac{11.2}{2}
=5+1/1.6666666666667
$