How can you calculate the Price and Quantity at a market equilibrium given the Demand curve P = 20 - Q and the Supply curve P = 3Q

To find the equilibrium point in a market you must make the supply and demand curve equal to one another. This means setting 20 - Q equal to 3Q and solving the simultaneous equations:20 - Q = 3Q20 = 4QQ = 5 => Demand Curve P = 20 - (5) => P = 15Therefore at market equilibrium the Quantity supplied would be 5 and this would be sold at price 15.