SOLUTION: 4 years ago Bob's age was the square root of his age within 2 years. Determine Bob's current age

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Question 1186179: 4 years ago Bob's age was the square root of his age within
2 years. Determine Bob's current age

Found 2 solutions by greenestamps, ikleyn:
Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


Sorry....

"...the square root of his age within 2 years" is not English.

Re-post giving the information clearly.


Answer by ikleyn(52786) About Me  (Show Source):
You can put this solution on YOUR website!
.

I agree with @greenestamps regarding English in this post.

So, the problem, as it is worded, deserves to be rejected.


But  I  made a  SUPER-effort.  Brilliant idea came to my mind,  and  I  guessed its hidden meaning.


It is to say

    Bob's age 4 years ago  is numerically the same 
    as the square root of his age two years from now.


In this formulation, we write this equation

    x - 4 = sqrt%28x%2B2%29.


Then we square both sides

    x^2 - 8x + 16 = x + 2


and simplify it

    x^2 - 9x + 14 = 0

    (x-7)*(x-2) = 0.


Of the two roots,  x= 7  and  x= 2,  the smaller root does not work (due to obvious reason: it is too small), and we reject it.


The greater root, x= 7, works and gives the ANSWER:  Bob is 7 years old now.

Solved.