Consider the following hypothetical reaction: 

2 L(g) + M(g) ⇌ 2 N(g)         K_c = 0.85

A 1.00 L flask is charged with 1.50 mol of compound N and allowed to reach equilibrium. The equation derived from the ICE chart is a cubic equation that cannot be solved in closed form. Estimate the equilibrium concentrations of L, M, and N by plotting the cubic equation. [Note: Make sure that the value of x will produce a positive concentration.]