2a-8a=12-8a
now add 8a to both side and you get
2a= 12
divide both sides by 2 and you get
a=6
        
                    
             
        
        
        
Hello! My work for this problem is attached below. The answer is 
Vb = 4Va
 
        
        
        
Answer:
x = -14
(っ◔◡◔)っ ♥ Hope It Helps ♥
 
        
                    
             
        
        
        
Answer:
Graph the trigonometric function using the amplitude, period, phase shift, and vertical shift.
Amplitude:  1
Period:  π
Phase Shift: 0  (
0  to the right)
Vertical Shift: 1
 
        
             
        
        
        
Answer:
Number of messages sent by Chau = 15
Number of messages sent by Kareem = 4 * 15 = 60
Number of messages sent by Jessica = 15 - 6 = 9
Step-by-step explanation:
Let number of messages sent by Chau = c
Number of messages sent by Kareem = 4 times as Chau 
                                                                 = 4 * c = 4c
Number of messages sent by Jessica = 6 fewer messages than Chau
                                                                = c - 6
Total messages = 84
<u>c + 4c + c</u> - 6 = 84                {Combine like terms}
<u>6c</u> - 6 = 84         {Add 6 to both sides}
6c  = 84 + 6 
6c = 90   {Divide both sides by 6}
c = 90/6
c = 15
Number of messages sent by Chau = 15
Number of messages sent by Kareem = 4 * 15 = 60
Number of messages sent by Jessica = 15 - 6 = 9