Question 220553:   If f(x-2)=6x-7, what is f(x)? 
 
The answer is f(x)=6x+5, but I have no idea how the answer is found! I keep ending up with 6x-17. Here is what I did....
 
f(x)= 6(x-2)+2-7 
f(x)= 6x-12-5 
f(x)= 6x-17
 
Please help! I think you're supposed to add 2 somewhere but I don't know where, why or how! 
 Found 2 solutions by  stanbon, MathTherapy: Answer by stanbon(75887)      (Show Source): 
You can  put this solution on YOUR website! If f(x-2)=6x-7, what is f(x)?  
The answer is f(x)=6x+5 
----------------------------- 
The original equation was shifted 2 units to the right to get 
f(x-2) = 6x-7 
---------------------- 
So shift it 2 units to the left to get back to f(x) 
f(x) = 6(x+2)-7 
f(x) = 6x+12-7 
f(x) = 6x+5 
======================= 
Cheers, 
Stan H. 
 Answer by MathTherapy(10557)      (Show Source): 
You can  put this solution on YOUR website! If f(x - 2) = 6x  7, what is f(x)?
 
 
Since we need the right side of the equation in f(x  2) = 6x - 7 to contain the binomial (x  2), we have to fix it to make it that way.
 
 
Since we have 6x  7 on the right-hand side of the equation, and we need to the binomial (x  2), we then need to subtract 5, and then add 5 to the right side. In other words,
 
 
f(x - 2) = 6x  7 now becomes: f(x - 2) = 6x  7  5 + 5. 
 
 
As seen, 5 was subtracted, and then added to the right-side to adjust but not change the equation.
 
 
Now, f(x - 2) = 6x  7  5 + 5 can be rewritten as: f(x - 2) = 6x  12 + 5, which can again be rewritten as f(x - 2) = 6(x  2) + 5. 
 
 
Now, since f(x - 2) = 6(x  2) + 5, then f(x)  =  6(x) + 5, or:  
 
 
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