To solve this problem you must apply the procceddure shown below:
 1. You have the following system of equations:
<span>
 x+y = 3 
 2x–y = 6
 2. Then, you must clear the variable y from the first equation and susbtitute it into the second equation, as below:
 x+y=3
 y=3-x
 2x-y=6
 2x-(3-x)=6
 2x-3+x=6
 3x=6+3
 3x=9
 3. Therefore, the value of x is:
 x=9/3
 x=3
 4. As you can see, the correct answer is:
 x=9
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Answer: If I remember correctly, the answer should be <em>y=-2(3)^x.  </em>
 
        
             
        
        
        
Answer:
68
Step-by-step explanation:
Add all of the numbers together then divide by the amount of numbers there are.