Answer: a = -15
Step-by-step explanation:
3a + b = 9
b=54
3a + 54 = 9
3a = 9-54
3a= -45
<h3>

</h3>
- x + = -
<h2>a= -15</h2>
 
        
             
        
        
        
Answer:
90
Step-by-step explanation:
100-10=90
 
        
             
        
        
        
Answer:

Step-by-step explanation:
So we have the system of equations: 

And we want to multiply the first equation by some constant such that the resulting equation matches the coefficient of [x] in the second equation. 
We can see that the coefficient of x in the second equation is 15. 
So, to match 15, we must multiply the first equation by 3. So: 

Multiply: 

And we're done!
 
        
                    
             
        
        
        
Answer:
12^x
Step-by-step explanation:
Absolute. Value. Of. |12^x-8|. Is. 12^x + 8
12^x + 8= 2^3.  So. 12^x. +8.=8
12^x+8-8=8-8
12^x=0. Left. With. 12^x?