SOLUTION: the sum of my age and your age is 20. in five years, twice my age will equal 9 more than your age. find my age and your age..

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Question 682053: the sum of my age and your age is 20. in five years, twice my age will equal 9 more than your age. find my age and your age..
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
let +a+ = my age
Let +b+ = your age
+a+%2B+5+ = my age in 5 yrs
+b+%2B+5+ = your age in 5 yrs
given:
(1) +a+%2B+b+=+20+
(2) +2%2A%28+a+%2B+5+%29+=+b+%2B+5+%2B+9+
---------------------------
(1) +b+=+20+-+a+
Substitute (1) into (2)
(2) +2%2A%28+a+%2B+5+%29+=+b+%2B+14+
(2) +2%2A%28+a+%2B+5+%29+=+20+-+a+%2B+14+
(2) +2a+%2B+10+=+34+-+a+
(2) +3a+=+34+-+10+
(2) +3a+=+24+
(2) +a+=+8+
and, since
(1) +a+%2B+b+=+20+
(1) +8+%2B+b+=+20+
(1) +b+=+12+
I am 8 and you are 12
check:
(2) +2%2A%28+a+%2B+5+%29+=+b+%2B+14+
(2) +2%2A%28+8+%2B+5+%29+=+12+%2B+14+
(2) +2%2A13+=+26+
(2) +26+=+26+
OK