which relation is a function?

The relation that is a function is:
b. y = 2x² - 3x + 7
A relation is a function if each value of the input is mapped to only one value of the output.
Hence, when both x and y are squared, we have that [tex]x = \pm ay[/tex], hence it is not a function. This is the case for items a and c.
For item d, we have that the relation can be simplified as follows:
x = -y² + 3y
x = y(-y + 3)
The solution above, is associated to two values of y, hence it is also not a function. Then the function is given by:
b. y = 2x² - 3x + 7
In the solution, it can be seen that for each input x, only one value of y can be generated.
More can be learned about relations and functions at brainly.com/question/12463448
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