(100x)+(200x*2x)=168

Solution for (100x)+(200x*2x)=168 equation:

(100x)+(200x*2x)=168

We move all terms to the left:

(100x)+(200x*2x)-(168)=0

We add all the numbers together, and all the variables

100x+(+200x*2x)-168=0

We get rid of parentheses

100x+200x*2x-168=0

Wy multiply elements

400x^2+100x-168=0

a = 400; b = 100; c = -168;
Δ = b2-4ac
Δ = 1002-4·400·(-168)
Δ = 278800
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{278800}=\sqrt{400*697}=\sqrt{400}*\sqrt{697}=20\sqrt{697}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(100)-20\sqrt{697}}{2*400}=\frac{-100-20\sqrt{697}}{800}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(100)+20\sqrt{697}}{2*400}=\frac{-100+20\sqrt{697}}{800}
$