SOLUTION: If sqr(6+4sqr2) = sqrx + sqry, x and y are rational, find x and y

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Question 1108428: If sqr(6+4sqr2) = sqrx + sqry, x and y are rational, find x and y
Answer by math_helper(2461) About Me  (Show Source):
You can put this solution on YOUR website!
+sqrt%286%2B4sqrt%28%282%29%29%29+=+sqrt%28x%29+%2B+sqrt%28y%29+
Squaring both sides:
+++6%2B4%2Asqrt%28%282%29%29++=++x+%2B+2sqrt%28x%29sqrt%28y%29+%2B+y+
++6%2Bsqrt%2832%29+=++x+%2B+2sqrt%28x%29sqrt%28y%29+%2B+y+
+4%2B2sqrt%284%2A2%29%2B2+=++x+%2B+2sqrt%28x%29sqrt%28y%29+%2B+y+
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Ans: x=4, y=2 (or equivalently x=2, y=4)
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