0.2x(x+90)+0.2x=22

Solution for 0.2x(x+90)+0.2x=22 equation:

0.2x(x+90)+0.2x=22

We move all terms to the left:

0.2x(x+90)+0.2x-(22)=0

We add all the numbers together, and all the variables

0.2x+0.2x(x+90)-22=0

We multiply parentheses

0x^2+0.2x+0x-22=0

We add all the numbers together, and all the variables

x^2+1.2x-22=0

a = 1; b = 1.2; c = -22;
Δ = b2-4ac
Δ = 1.22-4·1·(-22)
Δ = 89.44
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{-(1.2)-\sqrt{89.44}}{2*1}=\frac{-1.2-\sqrt{89.44}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(1.2)+\sqrt{89.44}}{2*1}=\frac{-1.2+\sqrt{89.44}}{2}
$