# Math Help - Supply and Demand

1. ## Supply and Demand

Suppose that the supply and demand equations of a certain commodity are given by q=5p-15 and q=-2.5p+30 respectively, where p is the unit price of the commodity in dollars and q is the quantity.

A. Beginning with the general equation derive what the supply is when the price is $8? B. Beginning with the general equation derive what the demand is when the price is$8.
C.Algebraically find the equilibrium price and the corresponding number of units supplied and demanded.
D. Draw the proper graphs of the supply and demand equations on the same set of axis.
E. Find where the two lines cross the horizontal axis and give an economic and physical interpretation of these points.