Ineed and if u can give me ways to solve the answer plz and thx

Okay so there are a few ways you can go about doing this.

Step-by-step explanation:

For number 1 you could say 5 - 7 = -2. I don't know if you need to use the same numbers for both the equations in number one, but 5 x -7 could work too.

For number 2 you could say 2 + 2 = 4 or 3 + 1 = 4. As for __ x __ = -5 you could say 2.5 x -2.5 = -5.

The rule is if you multiply a positive by a negative you get a negative. Just like if you multiply a negative by a negative you get a positive. And if you multiply a positive by a positive you get a positive.  

I really hope this helps since it took me a while to understand what you were asking.