SOLUTION: For what value of k is 49x^2-36x+k a perfect square

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Question 1121286: For what value of k is 49x^2-36x+k a perfect square
Found 2 solutions by josgarithmetic, Edwin McCravy:
Answer by josgarithmetic(39618) About Me  (Show Source):
Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
    (A+B)² = A²+2AB+B²

49x²-36x+k = A²+2AB+B²  

So we equate the corresponding terms

   A²=49x²,    2AB=-36x,     k=B² 
    A=7x  , 
            2(7x)B=-36x
              14Bx=-36x
               14B=-36
                 B=-36/14
                 B=-18/7
                            k=(-18/7)²
                            k=324/49

Edwin