Y=8 (-1, ) what would be my other number in parenthesis i already know -1.

This is so easy that it's confusing, and NOBODY ever gets it right
the first time they see it.

Inside the parentheses are two numbers.  The first number is a value
for 'x', and the second number is a value for 'y', and they have to be
numbers that when you put them into the equation in place of 'x' and 'y',
the equation becomes a true statement.

In this problem, you already know what 'x' is ... it's -1 .  Now, can you find
a value for 'y' that makes the equation true ?

Let me ask you that question again.  It's very, very important:
The equation is . . . . . Y = 8 . . . . . Can you find a value for 'y' that makes
this equation a true statement ?

Do you give up ?

Well, how about ' 8 ' ?
If you put ' 8 ' in place of 'y' in the equation, then the equation says . . . 8 = 8 . . . and that's true !

In fact, if you put any other number except '8' in place of 'y', then the
equation is not true.  'Y' must be 8 .  It doesn't matter what 'x' is.
'X' is not even in the equation. It has no effect on 'y'. 

'X' and 'y' don't even know about each other.  They're not related in
any way, and nobody cares what 'x' is.

'Y' is ALWAYS 8 ... that's exactly what the equation is telling you . . . Y = 8 .