Question 686945
Find all integers k such that the trinomial is a perfect square trinomial 
64x(squared) + kxy + y (squared) 
So am I just replacing k ? 
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Yes, solve for "k":
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Your Problem:
(8x)^2 + kxy + y^2
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Perfect Square Form: a^2 + 2ab + b^2
Your Problem:
a = 8x ; b = y
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Middle term has to be 2ab = 2(8x)y = 16xy
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So k has to be 16
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Cheers,
Stan H.
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