SOLUTION: Jack is 2 times as old as Lacy. 8 years ago the sum of their ages was 14 . How old are they now?

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Question 1118385: Jack is
2
times as old as Lacy.
8
years ago the sum of their ages was
14
. How old are they now?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +a+ = Jack's age now
Let +b+ = Lacy's age now
----------------------------------
(1) +a+=+2b+
(2) +%28+a+-+8+%29+%2B+%28+b+-+8+%29+=+14+
----------------------------------
(2) +a+%2B+b+-+16+=+14+
(2) +a+%2B+b+=+30+
Plug (1) into (2)
{2} +2b+%2B+b+=+30+
(2) +3b+=+30+
(2) +b+=+10+
and
(1) +a+=+2b+
(1) +a+=+2%2A10+
(1) +a+=+20+
-----------------------
Jack is 20
Lacy is 10
----------------
check:
(2) +%28+a+-+8+%29+%2B+%28+b+-+8+%29+=+14+
(2) +%28+20+-+8+%29+%2B+%28+10+-+8+%29+=+14+
(2) +12+%2B+2+=+14+
(2) +14+=+14+
OK