Principle 3 Law of demand. verbally state the law of demand: If the unit price of some specific product X falls, then the maximum quantity of this product X buyers are willing and able to buy (quantity demanded for product Price of product X X, abbreviated as qad) will Now explain how the movement along the market P1 demand curve from point A to point B graphically states the law of demand: the movement from point A to I P 2 point B states if the price of X falls from P.' to P,? then quantity demanded for product X (qxd) will: Demand 0 q di q, d2 quantity if product state the law of