document.write( "Question 421332: In right triangle ABC, CD is the altitude drawn to hypotenuse AB. AD is 2 units less than DB, and CD=3. In this triangle, which statement is true:\r
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Algebra.Com's Answer #294268 by Edwin McCravy(20086)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Right triangles ABC, ACD, and CBD are all similar.\r\n" );
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document.write( "Therefore since ACD and CBD are similar,\r\n" );
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document.write( "      x - 2     3\r\n" );
document.write( "     ——————— = ———\r\n" );
document.write( "        3       x\r\n" );
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document.write( "Cross multiply:\r\n" );
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document.write( "    (x - 2)x = 3*3\r\n" );
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document.write( "     x² - 2x = 9\r\n" );
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document.write( " x² - 2x - 9 = 0\r\n" );
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document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"\r\n" );
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document.write( "\"x+=+%282+%2B-+sqrt%284%2B36+%29%29%2F%282%2A%281%29%29+\"\r\n" );
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document.write( "\"x+=+%282+%2B-+sqrt%2840%29%29%2F2+\"\r\n" );
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document.write( "\"x+=+%282+%2B-+sqrt%284%2A10%29%29%2F2+\"\r\n" );
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document.write( "\"x+=+%282+%2B-+2sqrt%2810%29%29%2F2+\"\r\n" );
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document.write( "\"x+=+%282%281+%2B-+sqrt%2810%29%29%29%2F2+\"\r\n" );
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document.write( "\"x+=+%28cross%282%29%281+%2B-+sqrt%2810%29%29%29%2Fcross%282%29+\"\r\n" );
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document.write( "\"x+=+1+%2B-+sqrt%2810%29+\"\r\n" );
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document.write( "So DB has length \"1%2Bsqrt%2810%29\" or about 4.162\r\n" );
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document.write( "CD is given to be 3, so since 3 is less than DB, which is 4.162.\r\n" );
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document.write( "Therefore CD is less than DB, choice 1)\r\n" );
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document.write( "Edwin
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