1. (2,4)
2. (-∞, -5)
3. (-9, ∞)
I think I am over-thinking it
These are not ordered pairs! Interval notation provide just another way to indicate a range of numbers. Brackets mean "including", and parentheses mean "not including". You can also rewrite intervals as compound inequalities.
Take a look:
is
is
is
is
is
is
is
is
We never use brackets next to infinity or negative infinity.
Now try rewriting your intervals as inequalities.
I don't have a scanner but I send you to the link of the piece of paper. Its a PDF file. I am 100% it is not a bad photocopy/print-out.
Here is the link. Page 3.
http://susd.desertmountain.schoolfus...682007b4f66e36