SOLUTION: In 2011, Julie will be the same age as the square of her age in 2005. How old is Julie in 2008?

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Question 1106166: In 2011, Julie will be the same age as the square of her age in 2005. How old is Julie in 2008?
Found 2 solutions by josgarithmetic, greenestamps:
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
time 0, year 2005
time 3, year 2008
time 6, year 2011

j, Julie's age at time 0.
At time 6, Julie will be j^2.
j%2B6=j%5E2
-
j%5E2-j-6=0
%28j%2B2%29%28j-3%29=0
j=3----------Julie's age at time 0, year 2005.

Julie in 2008, 3 years greater than j;
3%2B3=highlight%286%29

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


If a formal algebraic solution is not required, try common sense, a little logical reasoning, and some simple mental arithmetic.

(1) Julie's age in 2011 is the square of her age in 2005, 6 years earlier.
(2) What number is there for which the difference between the number and the square of the number is 6?
(3) Answer: 3. 3 squared is 9, which is 6 more than 3.
(4) So Julie's age in 2005 was 3 and in 2011 it was 9.
(5) So in 2008 her age was 6.