SOLUTION: A man is 8 years older than his wife and 6 times as old as his son. When the son was born, the age of the wife was four-fifth of her husband. Find the age of the sun now. please us

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Question 1130158: A man is 8 years older than his wife and 6 times as old as his son. When the son was born, the age of the wife was four-fifth of her husband. Find the age of the sun now. please use linear equation thanks
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +a+ = the man's age now
Let +b+ = his wife's age now
Let +c+ = his son's age now
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(1) +a+=+b+%2B+8+
(2) +a+=+6c+
(3) +b+-+c+=+%284%2F5%29%2A%28+a+-+c+%29+
---------------------------------------
(1) +b+=+a+-+8+
(1) +b+=+6c+-+8+
-------------------------
By substitution:
(3) +6c+-+8+-+c+=+%284%2F5%29%2A%28+6c+-+c+%29+
(3) +5%2A%28+5c+-+8+%29+=+4%2A5c+
(3) +25c+-+40+=+20c+
(3) +5c+=+40+
(3) +c+=+8+
The son is 8
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check:
(2) +a+=+6c+
(2) +a+=+48+
and
(1) +b+=+6%2A8+-+8+
(1) +b+=+48+-+8+
(1) +b+=+40+
and
(3) +b+-+c+=+%284%2F5%29%2A%28+a+-+c+%29+
(3) +40+-+8+=+%284%2F5%29%2A%28+48+-+8+%29+
(3) +32+=+%284%2F5%29%2A40+
(3) +32+=+32+
OK