document.write( "Question 1121286: For what value of k is 49x^2-36x+k a perfect square \n" ); document.write( "
Algebra.Com's Answer #737106 by Edwin McCravy(20059)![]() ![]() You can put this solution on YOUR website! \r\n" ); document.write( " (A+B)² = A²+2AB+B²\r\n" ); document.write( "\r\n" ); document.write( "49x²-36x+k = A²+2AB+B² \r\n" ); document.write( "\r\n" ); document.write( "So we equate the corresponding terms\r\n" ); document.write( "\r\n" ); document.write( " A²=49x², 2AB=-36x, k=B² \r\n" ); document.write( " A=7x , \r\n" ); document.write( " 2(7x)B=-36x\r\n" ); document.write( " 14Bx=-36x\r\n" ); document.write( " 14B=-36\r\n" ); document.write( " B=-36/14\r\n" ); document.write( " B=-18/7\r\n" ); document.write( " k=(-18/7)²\r\n" ); document.write( " k=324/49\r\n" ); document.write( "\r\n" ); document.write( "Edwin\n" ); document.write( " |