Question 1174349
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Lance and Lexi are playing a number-guessing game. Lance asks Lexi to 
think of a positive number, triple the number, square the result, and then 
add 7. If Lexi’s answer is 43, what was the original number? Use the 
concept of inverse function in your solutions.
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<pre>
Moving backward,


(1)  subtract 7 from 43.  Get  43-7 = 36.



(2)  Take the square root of 36.  Get  {{{sqrt(36)}}} = 6.

                                  (we accept only POSITIVE square root, according to the condition).



(3)  Divide 6 by 3.   Get  {{{6/3}}} = 2.   


It is the <U>ANSWER</U>.  
</pre>

Do not accept any other answer, since any other number is INCORRECT.


Solved.