document.write( "Question 892250: Im having problems with this equation:\r
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document.write( "Two sets of quadratic expressions are shown below in various forms:\r
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document.write( "Line 1: x2 + 3x + 2 (x + 1)(x + 2) (x + 1.5)2 − 0.25
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document.write( "Line 2: x2 + 5x + 6 (x + 2)(x + 3) (x + 2.5)2 + 6.25\r
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document.write( "Which line contains three equivalent expressions? \r
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document.write( "Line 1 only \r
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document.write( "Line 2 only \r
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document.write( "Both Line 1 and Line 2 \r
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document.write( "Neither Line 1 nor Line 2 \r
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Algebra.Com's Answer #540392 by Edwin McCravy(20055)![]() ![]() You can put this solution on YOUR website! \r\n" ); document.write( "Line 1: x² + 3x + 2, (x + 1)(x + 2), (x + 1.5)² − 0.25\r\n" ); document.write( "Line 2: x² + 5x + 6, (x + 2)(x + 3), (x + 2.5)² + 6.25\r\n" ); document.write( "\r\n" ); document.write( "If two expressions are equivalent, then no matter what number\r\n" ); document.write( "we substitute into them, they will always simplify to the\r\n" ); document.write( "same numbers.\r\n" ); document.write( "\r\n" ); document.write( "So let's check by substituting a value, say, x=0 in each:\r\n" ); document.write( "\r\n" ); document.write( "Line 1: 0² + 3(0) + 2, (0 + 1)(0 + 2), (0 + 1.5)² − 0.25\r\n" ); document.write( "Line 1: 2, 2, 2.25 − 0.25\r\n" ); document.write( "Line 1: 2, 2, 2 \r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( "Line 2: 0² + 5(0) + 6, (0 + 2)(0 + 3), (0 + 2.5)² + 6.25\r\n" ); document.write( "Line 2: 6, 6, 6.25 + 6.25\r\n" ); document.write( "Line 2: 6, 6, 12.50\r\n" ); document.write( "\r\n" ); document.write( "Looks like the answer is Line 1 only. We have eliminated Line 2.\r\n" ); document.write( "\r\n" ); document.write( "But we can't be sure about Line 1. That's because it might \r\n" ); document.write( "have just been an accident that we got the same. So let's \r\n" ); document.write( "substitute x=1 in each:\r\n" ); document.write( "\r\n" ); document.write( "Line 1: 1² + 3(1) + 2, (1 + 1)(1 + 2), (1 + 1.5)² − 0.25\r\n" ); document.write( "Line 1: 1+3+2, 2·3, (2.5)² − 0.25\r\n" ); document.write( "Line 1: 6, 6, 6.25 - 0.25 \r\n" ); document.write( "Line 1: 6, 6, 6\r\n" ); document.write( "\r\n" ); document.write( "Yes it's probably Line 1 only. For it's not \r\n" ); document.write( "likely that we'd have run into two \r\n" ); document.write( "accidents.\r\n" ); document.write( "\r\n" ); document.write( "Try x = 2\r\n" ); document.write( "\r\n" ); document.write( "Line 1: 2² + 3(2) + 2, (2 + 1)(2 + 2), (2 + 1.5)² − 0.25\r\n" ); document.write( "Line 1: 4+6+2, 3·4, (3.5)² − 0.25\r\n" ); document.write( "Line 1: 12, 12, 12,25 - 0.25 \r\n" ); document.write( "Line 1: 12, 12, 12\r\n" ); document.write( "\r\n" ); document.write( "No doubt about it. It's Line 1 only.\r\n" ); document.write( "\r\n" ); document.write( "Edwin\n" ); document.write( " |