document.write( "Question 259986: give exact and approximate solutions to three decimal places: y^2-8y+16=1 \n" ); document.write( "
Algebra.Com's Answer #191434 by Edwin McCravy(20055)\"\" \"About 
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give exact and approximate solutions to three decimal places: y^2-8y+16=1
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document.write( "\"y%5E2-8y%2B16=1\"\r\n" );
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document.write( "Subtract 1 from both sides to get 0 on the right side:\r\n" );
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document.write( "\"y%5E2-8y%2B15=0\"\r\n" );
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document.write( "You can factor that as\r\n" );
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document.write( "\"%28y-3%29%28y-5%29=0\"\r\n" );
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document.write( "Set each equal to 0:\r\n" );
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document.write( "\"y-3=0\"\r\n" );
document.write( "\"y=3\"\r\n" );
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document.write( "\"y-5=0\"\r\n" );
document.write( "\"y=5\"\r\n" );
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document.write( "But since you mentioned decimal approximating that\r\n" );
document.write( "made me think you were supposed to do it using\r\n" );
document.write( "the quadratic formula:\r\n" );
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document.write( "You would use \"y\" for \"x\", \"1\" for \"a\",\r\n" );
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document.write( "\"-8\" for \"b\" and \"15\" for \"c\"\r\n" );
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document.write( "\"y%5E2-8y%2B15=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+=+%28-%28-8%29+%2B-+sqrt%2864-60+%29%29%2F2+\"\r\n" );
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document.write( "  \"x+=+%288+%2B-+sqrt%284%29%29%2F2+\"\r\n" );
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document.write( "  x = (8±2)/2 \r\n" );
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document.write( "Using the +,\r\n" );
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document.write( "  \"x+=+%288+%2B+2%29%2F2+\"\r\n" );
document.write( "  \"x+=+10%2F2+\"  \r\n" );
document.write( "  \"x=5\"\r\n" );
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document.write( "Using the -,\r\n" );
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document.write( "  \"x+=+%288+-+2%29%2F2+\"\r\n" );
document.write( "  \"x+=+6%2F2+\"  \r\n" );
document.write( "  \"x=3\"\r\n" );
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document.write( "Edwin
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