It might be a stupid question, but on exercise 6 about plugging in, I plugged in 3 for x, and none of the answer choices were correct. Letter c was the closest, but still, 3 raised to 6 equals 729; minus 9 equals 720. okay, but the result for letter c, if y=9, is 72.
So, I wanted to ask you if, on this specific exercise, the only option to get the right aswer is plugging in 2 for x.
(sorry if I said any terms in the wrong way, engish is not my first language)

Here’s the question for everyone else playing along:

I think the problem is that you’re squaring x instead of cubing it. If you’re plugging in x = 3, then you should have x^3=3^3=27 for y and x^6-x^3 should be 3^6-3^3=729-27=702.

So you’re looking for an answer choice that equals 702 given y = 27. Choice C works: 27(27 - 1) = 702.