SOLUTION: 11 years ago Hye was four times as old as her brother. In 1 year she will be twice as old as he is. What are their ages now?

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Question 126738: 11 years ago Hye was four times as old as her brother. In 1 year she will be twice as old as he is. What are their ages now?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let b = brother's age today
Let h = her age today
h+-+11+=+4%28b+-+11%29
h+%2B+1+=+2%28b+%2B+1%29
------------------------
h+-+11+=+4b+-+44
h+-+4b+=+-33
------------------------
h+%2B+1+=+2b+%2B+2
h+-+2b+=+1
------------------------
So, now I have
h+-+4b+=+-33
h+-+2b+=+1
multiply the 2nd equation by -1 and add them
h+-+4b+=+-33
-h+%2B+2b+=+-1
------------------
-2b+=+-34
b+=+17
h+-+2b+=+1
h+=+2b+%2B+1
h+=+2%2A17+%2B+1
h+=+35
She is 35 and he is 17
check:
h+-+11+=+4%28b+-+11%29
35+-+11+=+4%2817+-+11%29
24+=+24
OK
h+%2B+1+=+2%28b+%2B+1%29
35+%2B+1+=+2%2A18
36+=+36
OK