-4^4= -4*-4*-4*-4
-4*-4=16
16*-4=-64
-64*-4= 256
Final answer: 256
        
             
        
        
        
By substitution is how to solve
2x-3y=21
y=3-x
2x-3(3-x)=21 
2x-9+3x=21
5x=30
x= 6
now substitute our x value into y=3-x
so we get 
y=3-6 = -3
so x=6 and y=-3  hope this helps!!!!! Thank you!
        
                    
             
        
        
        
(6 times 2x) + (6 times 5y)
        
             
        
        
        
Answer:
x=-3y+8
Step-by-step explanation:
2x+6y=16
2x=16-6y
2x=-6y+16
x=-6/2y+16/2
x=-3y+8