Calculating equilibrium concentrations given only Kc?

[Brittney McCown 1C]

I am looking at 11.61 part c. and I can't figure out how to calculate the equilibrium concentrations of each substance given only the K value. Send help

[Andrea Zheng 1H]

Given only K, you would have to make an ICE table and then use the final equilibrium line from your table in the expression for K (K=[eq line of products]/[eq line of reactant 1][eq line of reactant 2]). Because you are given the K value, you would set the expression equal to the K value of 0.56. You would then multiply out the equation and use the quadratic formula to obtain the value of x. This x value (the one that is possible based on the problem) is then used in the original expressions obtained in the equilibrium line of the ICE table to get the final composition at equilibrium.

I didn't include numbers in the explanation because I thought it might get more confusing but hopefully this makes sense!