I did the problem, and got 8, it said it was incorrect. I then tried negative 8 but didn’t work again, so I’ve been searching it up everyone, and it always says 8 or -8. so are my answering right or not?

Given the function:
[tex]f(x)=x^2-2x[/tex]to find f(-4), we have to make x = -4 and substitute on the expression that represents the function. In this case, we have the following:
[tex]undefined[/tex]