If y represents price (measured in dollars) and times represents quantity purchased then what is the area or size of the triangle you see in the graph Economic application -- Say you wanted to place a tax on a product that has this demand curve and in which price was $75. What would the revenue be raised by the tax (answer=$500) and the traingle represents lost value from the lesser amount available after the tax is imposed. So to raise $500 in tax revenue you lost how much in consumer value (answer---it is the area of the triangle) -$1,000 $250 500 2000/2 = $1,000