explain why each graph is or isnt a function
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Answer:
B and C are functions but A and D are not
Step-by-step explanation:
Vertical line testing. You draw a vertical line. If the vertical lines passes through one line, its a function. It it passes through more than one line, its not. Or in other words, each input (x-value) has its own output (y-value)
only c is a function.
a, b, and d all fail the vertical line test, meaning their x values can have multiple outputs.