SOLUTION: 5 years ago jay was 7 times older than Mary. In 5 years, Mary will be half as old as jay. How old is each now?

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Question 1020402: 5 years ago jay was 7 times older than Mary. In 5 years, Mary will be half as old as jay. How old is each now?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +j+ = Jay's age now
Let +m+ = Mary's age now
------------------------
(1) +j+-+5+=+7%2A%28+m+-+5+%29+
(2) +m+%2B+5+=+%281%2F2%29%2A%28+j+%2B+5+%29+
--------------------------
(1) +j+-+5+=+7m+-+35+
(1) +7m+-+j+=+30+
and
(2) +2m+%2B+10+=+j+%2B+5+
(2) +-2m+%2B+j+=+5+
-----------------------
Add (1) and (2)
(1) +7m+-+j+=+30+
(2) +-2m+%2B+j+=+5+
------------------
+5m+=+35+
+m+=+7+
and
(2) +-2m+%2B+j+=+5+
(2) +-2%2A7+%2B+j+=+5+
(2) +-14+%2B+j+=+5+
+j+=+19+
------------------
Mary is 7
Jay is 19
----------
check:
(2) +m+%2B+5+=+%281%2F2%29%2A%28+j+%2B+5+%29+
(2) 7+%2B+5+=+%281%2F2%29%2A%2819+%2B+5+%29+
(2) +12+=+%281%2F2%29%2A24+
(2) +12+=+12+
OK
You can check (1)