Answer: Choice D
which is the log base 6 of x
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Step-by-step explanation:
Since you're given a list of choices, you can plug in each x coordinate of the points shown and see what the y values are.
If you plugged x = 6 into choice A, you would end up with y = -1 but we want y = 1 instead. So choice A can be crossed off the list.
If you plugged in x = 6 into choice B, then you would get y = -2.6 approximately. So this answer won't work either.
Try x = 6 into choice C, and you'll get a division by zero error. So that can be crossed off too.
The only thing left is choice D. This function works because x = 0.5 leads to y = -0.4 approximately. Also, x = 1 and y = 0 pair up together. Similarly, the input x = 6 produces the output y = 1.
note: you may have to use the change of base formula to compute the log values. The change of base formula is log(b,x) = log(x)/log(b)