SOLUTION: A is 20years older than b.5years ago,a was 3 times as old as b.find their present ages.

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Question 687858: A is 20years older than b.5years ago,a was 3 times as old as b.find their present ages.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A is 20 years older than b. 5years ago,a was 3 times as old as b.
find their present ages.
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Equations:
a = b + 20
a-5 = 3(b-5)
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Substitute for "a" and solve for "b":
b+20-5 = 3(b-5)
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b+15 = 3b-15
2b = 30
b = 15 yrs (B's age now)
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Solve for "a" using a = b + 20
a = 15+20
a = 35 yrs (A's age now)
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Cheers,
Stan H.
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