For a function, each x term must correspond to exactly one y term. We can use the vertical line test to determine whether or not that holds true for the following 6 graphs. If each x term corresponds to exactly one y term, then any vertical line that we draw on the graph should hit the graph at only one point.
1. We can't draw a vertical line that hits the graph at more than one
point so this relation must be a function.
2. We can draw many vertical lines that will hit the graph at more than one point. Thus, we can conclude the graph shown here is not a function.
3. We can't draw a vertical line that hits the graph at more than one
point so this relation must be a function.
4. We can't draw a vertical line that hits the graph at more than one
point so this relation must be a function.
5. We can draw many vertical lines that will hit the graph at more than one point. Thus, we can conclude the graph shown here is not a function.
6. We can draw many vertical lines that will hit the graph at more than one point. Thus, we can conclude the graph shown here is not a function.
