Solve by elimination
x+y=7
x-y=9

The 1st thing you do is see if you have something that will cancel each other out which you do and it is Y so cancel those out and you combine like terms and get 2x=16 and then divide by 2 and get x=8. then you plug 8 in to your equation and get 8+y=7 and then subtract 8 from both sides and get y=-1. Your solutions are x=8 and y=-1. Hope this helps

I’m pretty sure it’s i think : /