Quiz 4

Date: MATH 1090-4 - Fall 2003

Note: Unless stated otherwise, answers without justification receive no credit. Please, show your work!

1. Graph the set determined by $3x+2y=6$. Make sure that your axes have labels and unit marks!

2. For each of the following lines, find the slope and intercepts (both $x$ and $y$-intercepts). If any of these elements does not exist, state it clearly.
   1. $x=-3$.
   2. $2x-3y=1$.
   3. $y=-3$.

3. Decide if the lines $y=3x-2$ and $x+3y=1$ are parallel, perpendicular, or neither.

4. The water company charges its customers, monthly, according to the following scheme: a base cost of $7 and an additional $ 0.01 for each gallon of water used.
   1. Write an equation for the monthly charge, $C$, as a function of the amount of water used, $W$.
   2. If, in addition, there is a 7% tax on water bills, what is the new equation for the charge as a function of the amount of water used?