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a woman is 3 times as old as her son.8 years ago the product of their ages was 112. find their present ages​

User Jon Wilson
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1 Answer

5 votes

Answer:

Son 12 and woman 36 years old.

Explanation:

Let the age of the woman now be 3x years, then her son's age = x years.

8 years ago the woman's age was (3x-8) and her son's age was (x- 8) years, so:

(3x - 8)(x - 8) = 112

3x^2 - 32x + 64 = 112

3x^2 - 32x - 48 = 0

3x^2 - 36x + 4x - 48 = 0

3x(x - 12) + 4(x - 12) = 0

(3x + 4)(x - 12 ) = 0

x = -1.33... , 12 . ( We ignore the negative value).

So the son's age is 12 and the woman's age is 36.

User Jack Murdoch
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