document.write( "Question 137873: can you please factor this problem for me and show how it is done:\r
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Algebra.Com's Answer #100781 by Edwin McCravy(20062)\"\" \"About 
You can put this solution on YOUR website!
can you please factor this problem for me and show how it is done:
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document.write( "Write this:\r\n" );
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document.write( "(x    )(x     )\r\n" );
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document.write( "Look at the 72 of \" x² + 6x - 72 \"\r\n" );
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document.write( "It is negative, so think \"SUBTRACT\". \r\n" );
document.write( "(If it had been positive you would think \"ADD\")\r\n" );
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document.write( "Look at the 6 of \" x² + 6x - 72 \".\r\n" );
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document.write( "Think of two whole numbers that when multiplied \r\n" );
document.write( "give 72 and, when SUBTRACTED, give 6?\r\n" );
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document.write( "Go thru pairs of integers which multiply to give \r\n" );
document.write( "72, and see if when you SUBTRACT them, larger\r\n" );
document.write( "minus smaller, you get 6.\r\n" );
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document.write( "72 = 1x72, but 72-1 = 70, not 6\r\n" );
document.write( "72 = 2x36, but 36-2 = 34, not 6\r\n" );
document.write( "72 = 3x24, but 24-3 = 21, not 6\r\n" );
document.write( "72 = 4x18, but 18-4 = 14, not 6\r\n" );
document.write( "72 = 6x12, and 12-6 = 6.  Hey that's it!\r\n" );
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document.write( "Now write just the 6 and the 12 at the \r\n" );
document.write( "right ends of those two parentheses:\r\n" );
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document.write( "So you have this now:\r\n" );
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document.write( "(x   6)(x   12) \r\n" );
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document.write( "Now look at the sign before the middle \r\n" );
document.write( "term of \" x² + 6x - 72 \". It is plus, \r\n" );
document.write( "so put a plus next to the larger number, \r\n" );
document.write( "which is 12.  So now you have\r\n" );
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document.write( "(x   6)(x + 12)\r\n" );
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document.write( "Now you only need to find what sign to \r\n" );
document.write( "put in the first parentheses.\r\n" );
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document.write( "Since the last term of \" x² + 6x - 72 \" \r\n" );
document.write( "is negative, put the OPPOSITE sign before \r\n" );
document.write( "the 6 that you put before the 12.  Since\r\n" );
document.write( "you oput a plus sign before the 12, you \r\n" );
document.write( "will put a minus sign before the 6. \r\n" );
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document.write( "(x - 6)(x + 12)\r\n" );
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document.write( "(If it were positive, you would have put \r\n" );
document.write( "the SAME sign instead.)\r\n" );
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document.write( "Edwin
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