Economic analysis of supply and/or demand

1. In the economic analysis of supply and/or demand the variables of interest are not X and Y but instead Price (P) and Quantity (Q). By convention P is always the vertical axis and Q is the horizontal axis. Below are algebraic representations of supply or demand functions. Graph each separately and beside your graph, list the Y-intercept and slope of each (and whether is a supply or demand equation). a. P= 500 – 100 b. 70Q + 7P = 3500 c. Q= 50 – 0.1P