Is someone trying to 'hook' me. I seee the answers immediately - is this so you can laugh at me (no harm intended)?
2 + 2 Just reverse the the first '2' remove the + sign and abut the first '2' against the second - lay the two sideways and there is your fish (singular).
3 + 3 In similar fashion - reverse the first '3' and abut it to the second '3' and there is your figure '8'
7 + 7 Follow the above procedure but instead of abutting the two figures - overlay the top bar of the figure '7' and, voila, there is your inverse triangle.