I think it’s p=36 because you have to do the opposite on both sides.. 
So.. 
q=-12
P/-12=-3
 +12 *12
P=36
        
                    
             
        
        
        
40%*2=80 I hope I helped!
        
             
        
        
        
Answer:
Step-by-step explanation:
the 2 friend eat 5/8
 
        
             
        
        
        
Step-by-step explanation:
The equation has 100, which represents the cost of the printer, then you add to .05p which stands for each page is .05 and you multiply it by p which would be the amount of pages, so when you do .05p it stands for the equation to to calculate the total cost of pages. Then .25p is the cost times the amount of pages. 
Hope this helps, you understand it more. 
 
        
             
        
        
        
Let the two numbers be x and y where x is greater than y.
So;
x + y = 3.1 ... (i)
2x - 3y = 7 ... (ii)
This forms a set of simultaneous equations (i) and (ii)
Solving the simultaneous equations by elimination;
We multiply (i) by 2 and (ii)  by 1 to get:
2x + 2y = 6.2 ... (i)
2x - 3y = 7 ... (ii)
Subtracting (i) - (ii) we get;
5y = -0.8
y = -0.8/5 = -0.16
x = 3.1 - -0.16 = 3.26
The numbers are 3.26 and -0.16.