C=0.2x^2-92x+11,170

Solution for C=0.2x^2-92x+11,170 equation:

=0.2C^2-92C+11.170

We move all terms to the left:

-(0.2C^2-92C+11.170)=0

We get rid of parentheses

-0.2C^2+92C-11.170=0

We add all the numbers together, and all the variables

-0.2C^2+92C-11.17=0

a = -0.2; b = 92; c = -11.17;
Δ = b2-4ac
Δ = 922-4·(-0.2)·(-11.17)
Δ = 8455.064
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$C_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$C_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$C_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(92)-\sqrt{8455.064}}{2*-0.2}=\frac{-92-\sqrt{8455.064}}{-0.4}
$
$C_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(92)+\sqrt{8455.064}}{2*-0.2}=\frac{-92+\sqrt{8455.064}}{-0.4}
$