Calculate the equilibrium partial pressures of the three

Question

Question:

Consider the formation of NO_(g) from its elements

N2(g) + O2(g) = 2NO(g)

Calculate the equilibrium partial pressures of the three gases at 700 ^oC if the initial partial pressures of N₂ and O₂are both 85 kPa.

Im just confused as to how to approach this problem because the value of Kp was not given.