Answer:
it is not because a polynomial cannot have a negative power
 
        
             
        
        
        
Answer:
90
Step-by-step explanation:
0.9 multiplied by 100 to turn it into a percentage is 90.
 
        
                    
             
        
        
        
The first thing we must do for this case is to define variables:
 We have then:
 x: liz's age
 y: melinda's age
 We now write the system of equations: 

 By solving the system graphically we have that the age of each one is currently: 

 Next year, the age of liz is: 
 Answer:
 Next year, Liz's age is 11 years.
 Note: see attached image for the graphic solution.
 
        
             
        
        
        
Answer:
See the attached pictures for answer. 
Step-by-step explanation:
See the attached picture for detailed explanation.
 
        
             
        
        
        
Answer:
y = 16, don't know if I'm 100% right but hope this helps.
Step-by-step explanation:
since they both equal Y they may be equal to each other 
Then you would subtract 2x from both sides canceling it out on one side 
2x + 8 = 5x - 4
-2x         -2x
This would make the equation 8 = 3x - 4
next you add the 4 from both sides 
8  = 3x - 4
+4         +4
This will leave you with 12 = 3x 
now you divide 3 from both sides and 12/3 = 4 makes X = 4 
next you take (4) and plug it in to one of the equations 
y = 2(4) + 8 
y = 8 + 8 
y = 16