I have plotted a graph with a demand curve equation of: Qd=40-2P
and a supply curve equation of: Qs=2/3P (two thirds)
The world price is 9. There is perfect competition in the market for this good.
I have to determine the quantity consumed and the quantity supplied domestically if there is free trade. Does anyone know how to calculate these two things?
Edit: I have found the equilibrium price to be 14.8. This is part of a second year University course btw.