SOLUTION: the sum ages of two brothers is 38.In three yrs time the age of the elder brother is the square if the younger brother

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Question 1063258: the sum ages of two brothers is 38.In three yrs time the age of the elder brother is the square if the younger brother
Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
system%28x%2By=38%2C%28x%2B3%29%5E2=y%2B3%29

Any solution found must be positive real numbers.

Age sum equation gives y=38-x. Substitute this into the other equation.

%28x%2B3%29%5E2=%2838-x%29%2B3
x%5E2%2B6x%2B9=38-x%2B3
x%5E2%2B7x%2B9-38-3=0
x%5E2%2B7x%2B9-41=0
highlight_green%28x%5E2%2B7x-32=0%29

General solution for quadratic equation:
x=%28-7%2B-+sqrt%2849-4%2A%28-32%29%29%29%2F2

x=%28-7%2B-+sqrt%28177%29%29%2F2

x=%28-7%2B-+13.304%29%2F2

The PLUS-form is needed because any solution must be a positive real number.

x=%28-7%2B13.304%29%2F2

highlight%28x=3.152%29------younger brother

Now find y.
y=38-x
y=38-3.152
highlight%28y=34.848%29-------older brother

These numbers are in years are mixed numbers in their decimal approximations.

CHECK TO BE SURE.
%28x%2B3%29%5E2=y%2B3
%283.152%2B3%29%5E2=34.848%2B3
6.152%5E2=37.848
37.847=37.848-----------close enough, okay.

Answer by ikleyn(52798) About Me  (Show Source):
You can put this solution on YOUR website!
.
This problem HAS NO solutions in integer numbers.


Question to the person who posted it: For what reason do you liter the forum with nonsense problems ?