Math Problem Statement

Does the graph represent a function and if so, why?

Yes, there is more than one ordered pair on this graph.

Yes, no two ordered pairs on this graph have the same first element.

No, there is a limited number of ordered pairs on this graph.

Yes, no two ordered pairs on this graph have the same second element.

Solution

To determine whether the graph represents a function, let's analyze it in the context of what a function is:

Definition of a Function:

A function is a relation between a set of inputs and a set of possible outputs where each input is related to exactly one output. In terms of a graph, this means that for each value of xx (the first element in the ordered pair), there is only one corresponding value of yy (the second element in the ordered pair).

Vertical Line Test:

One way to determine if a graph represents a function is to use the Vertical Line Test. If a vertical line intersects the graph at more than one point, then the graph does not represent a function.

Analysis of the Given Graph:

  • Line A: This line appears to pass the vertical line test (no vertical line would intersect it more than once).
  • Line B: Also passes the vertical line test.
  • Line C: This horizontal line passes the vertical line test.
  • Line D: This vertical line does not pass the vertical line test because any vertical line would intersect it at every point along that line.

Conclusion:

  • The graph as a whole does not represent a function because Line D is vertical. A vertical line represents multiple outputs (y-values) for a single input (x-value), which violates the definition of a function.

Answer to the Multiple-Choice Statement:

  • No, there is a limited number of ordered pairs on this graph. (This statement is incorrect because even with a limited number of ordered pairs, the graph can still represent a function as long as each input corresponds to exactly one output.)
  • Yes, there is more than one ordered pair on this graph. (This is true, but it doesn't address whether it represents a function.)
  • Yes, no two ordered pairs on this graph have the same first element. (This would indicate a function if all lines had different x-values for every y-value, but the vertical line D violates this.)
  • Yes, no two ordered pairs on this graph have the same second element. (This statement is not necessarily true for this graph and does not confirm whether it's a function.)

Thus, the correct conclusion is that the graph does not represent a function due to the presence of the vertical line, which fails the Vertical Line Test.

Would you like to explore this further or have any additional questions?


Here are 5 related questions you might consider:

  1. How would the graph change if Line D were not included?
  2. What happens to the function definition if two lines intersect at a single point?
  3. Can a graph with only horizontal lines represent a function?
  4. How can you modify a vertical line so that the graph becomes a function?
  5. Why is the Vertical Line Test a reliable method for determining whether a graph represents a function?

Tip: Always use the Vertical Line Test as a quick way to check if a graph represents a function. If any vertical line crosses the graph more than once, the graph does not represent a function.