SOLUTION: jane is 7 years older than amy. Twelves years ago, Amy was half as old as jane is now. How old is jane now?

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Question 1106480: jane is 7 years older than amy. Twelves years ago, Amy was half as old as jane is now. How old is jane now?
Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!
J = Jane's age now
A = Amy's age now

jane is 7 years older than amy. 
J = A + 7

Twelve years ago, Amy was...
Twelve years ago, Amy was A-12

Twelve years ago, Amy was half as old as jane is now. 
A-12+=+expr%281%2F2%29J 

So we have the system of equations:

system%28J+=+A+%2B+7%2CA-12+=+expr%281%2F2%29J%29

Multiply both sides of the second equation by 2:

system%28J+=+A+%2B+7%2C2A-24+=+J%29

How old is jane now?

Solve the system by substitution.  If you have trouble,
tell me in the message form below and I'll get back to 
by email.

Edwin