The graph of a proportional relationship is a line through the origin or a ray whose endpoint is the origin
3. No because it's a line that doesn't go through the origin
4. Yes because it's a line through the origin
5. Yes because 1/3 = 2/6 = 3/9 = 4/12
6. No because 4/2 isn't equal to 8/5
7. Draw a graph just like 4., but change the y-axis
8. a. Let the equation be y = ax. 27 = 3a. a = 9. Therefore the equation is y = 9x.
8. b. 9
8. c. 9 * 5 = 45
9. a. The car travels 25 (> 18) miles per gallon of gasoline.
9. b. 25 * 8 - 18 * 8 = 7 * 8 = 56