To determine whether a graph of a relation is also a function, Shayla declares that the y-axis is a vertical line and counts the number of times that the graph intersects the y-axis. If the graph has exactly one y-intercept, Shayla concludes that the graph shows a function. In all other cases, she declares that it is not a function. Is Shayla applying the vertical line test correctly?

Question

unklerhaukus · Answer

The are other vertical lines Shayla has to consider;
 if the relation crosses Any vertical line more than once it is not a function

anonymous · Answer

A. No, because the y-axis is a horizontal line.
B. No, because using the y-axis tests only whether x = 0 is mapped to multiple values.
C. Yes, because multiple y-intercepts represent multiple x-values being mapped to y = 0.
D. Yes, because the y-axis represents all vertical lines of the x-values.
which one is it please I need help

unklerhaukus · Answer

for example

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unklerhaukus · Answer

This relation fails the vertical line test because  f(x_1) maps to multiple y values 
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