The answer to your question would be 16
        
             
        
        
        
I tried my best for this I’m pretty for sure I remember doing this in school but I’m not for sure I hope this helped a little bit
 
        
        
        
Answer: 
Positive, because the products (3) × (−3) and (−2) × (4) are negative and the product of two negative numbers is positive.
Step-by-step explanation:
Since 1 * -1 = -1, and -1 * -1 = 1, the product of opposite signs produces negative numbers while the product of same signs produces positive numbers. So the product of 1 * 1 * 1 * -1 = -1, while -1 * -1 * -1 * -1 = 1.
 
        
             
        
        
        
They have different masses
        
             
        
        
        
Answer:
first I would combine terms which would give me 
-4x-7=-7-4x
then I would get the variable on each side of the equal sign
0=0
lastly I would verify the solution 
infinite solutions
Step-by-step explanation:
combining combining like terms would give you negative 4x - 7 which is equal to -7 - 4x. if you were to add 7 on either side and 4 on either side you would get 0 = 0 because this is correct it's infinite solutions