SOLUTION: the difference in the ages of two brother is 6 years.if after two years the product of their ages will be 280 find their present age

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Question 991055: the difference in the ages of two brother is 6 years.if after two years the product of their ages will be 280 find their present age
Answer by ikleyn(52786) About Me  (Show Source):
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Answer.  20  and  14 after  2 years; correspondingly,  18  and  12  is present age now.

The tip:  after two years the difference in their ages will be the same,  6 years.

Let  x  and  y  are their ages after  2  years.  Then you have the system

system%28x-y+=+6%2C%0D%0Axy=280%29.

Express  x  from the first equation, x = y+6, and substitute it into the second equation.  You will get

(y+6)*y = 280,

y%5E2 + 6y - 280 = 0.

The roots are  14  and  -20.

Only positive root suits the condition.

Next,  take off  2  years.