Answer:
3.
Step-by-step explanation:
3(n + 4) = 21
3n + 12 = 21
3n = 21 - 12 = 9
n = 3.
 
        
                    
             
        
        
        
Answer:
1. Read through the problem and figure out what it's about.
 Represent numbers you don't know with variables.
Translate the problem into a mathematical expression.
Solve the problem.
Check your work.
Step-by-step explanation:
 
        
             
        
        
        
Answer:I’m trying to find it too
Step-by-step explanation:I don’t know what it is but I’m sure it’s 12-90