Question 939990
today, a father is 10 years older than twice his son's age. five years a go, the product of their ages was 350. how old is his son now 
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Equations::
f = 2s+10
(f-5)(s-5) = 350
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Substitute for "f" and solve for "s"::
(2s+5)(s-5) = 350
2s^2 -5s -375 = 0
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s = 15 yrs (son's age now)
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Cheers,
Stan H.
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