Please help me solve this. I understand it in theory, but no matter how I plug in my numbers, I can never get the right answer. I have even used online calculators to confirm that I am calculating the correct standard formula. In this case, the standard formula I get is:

x^2 + 1.1592x - 0.2237

Is that correct? If so, then my mistake is in the next step (quadratic formula).

Please work out the quadratic formula portion step-by-step. Explain every little detail, if you have the time. I need to figure out where I'm going wrong!

Please and thank you.

Predict and calculate the effect of concentration changes on an equilibrium system.

Some PCl₅ is allowed to dissociate into PCl₃ and Cl₂ at 523 K. At equilibrium, [PCl₅] = 0.126 M, and [PCl₃] = [Cl₂] = 7.9610^-2 M. Additional PCl₅ is added so that [PCl₅]_new = 0.230 M and the system is allowed to once again reach equilibrium.

PCl₅(g) PCl₃(g) + Cl₂(g) K = 5.0110^-2 at 523 K

(a) In which direction will the reaction proceed to reach equilibrium? Right or left?

(b) What are the new concentrations of reactants and products after the system reaches equilibrium?

[PCl5]	=	____ M
[PCl3]	=	____ M
[Cl2]	=	____ M