Does this graph show a function? Explain how you know. 6 2 8 6 4 2 0 -2 4 6 8 6 -8 A. Yes, there are no y-values that have more than one x-value. B. Yes; the graph passes the vertical line test. C. No; the graph fails the vertical line test. D. No, there are y-values that have more than one x-value.

A function is a relationship that maps elements from a set (the domain, set of the inputs) into elements from another set (the range, set of the outputs), such that each element from the domain can be mapped into only one element from the range.

Remember that in the 2d case, the horizontal axis represents the values from the domain while the vertical axis represents the values from the range.

So, one criterion to check if a graph belongs to a function or not, is to see if there is a vertical line that intersects the graph at two different points, (because that would mean that a single input value has two different output values) if there is no vertical line that does that, then the graph shows a function. (this is called the vertical line test)

Now that we know all this, let's look at the graph for a second and see that yea, the graph passes the vertical line test, so the graph represents a function.

Then the correct option is B