Question 684180
Let T = age of Tom now
Let S = age of Tom's son now
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Given:
T = S + 25  (Tom is 25 yrs older than his son is now)
T + 10 = 3S - 5 (in 10 yrs, Tom will be 5 yrs younger than 3x his son's age)
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Method: with 2 equations and 2 variables, express one of the variables in terms of the other and solve:
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Take the equation with T = S + 25 and plug S + 25 into the 2nd equation for T:
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(S + 25) + 10 = 3S - 5
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Put all the S terms on one side and group all like-terms on the other:
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S + 35 = 3S - 5
40 = 2S
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divide both sides by 2:
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20 = S
T = S + 25
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Answer:
T = 45
S = 20
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Lee