Step-by-step explanation:
both halves of a diagonal must be equal.
so, 
8b - 30 = 6b + 6
2b = 36
b = 18
and
9a - 13 = 5a + 5
4a = 18
a = 18/4 = 4.5
 
        
             
        
        
        
Answer:
80 cents
Step-by-step explanation:
 
        
                    
             
        
        
        
63/12 = 4.2
4.2 x 12 = 50.4
x = 50.4
        
             
        
        
        
X= 6
Y= 0 
Z= -2
CHECK
3x + y -2z =22
3(6) + 0 -2(-2) =22
18 + 0 +4= 22
22=22
x+5y+z =4
6 +5(0)+ -2 =4
6 + 0 +-2 = 4
4=4
x+3z=0
6 + 3(-2) =0
6 -6 = 0
0=0
        
             
        
        
        
Answer:
may be 5 times is answer but I am not sure I have done 5 times I got like this