document.write( "Question 1032905: the father + the mother+ the sister+ the brother =
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Algebra.Com's Answer #647493 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
The father + the mother + the sister + the
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document.write( "F+M+S+B = 100\r\n" );
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document.write( "F² = M²+S²+B²\r\n" );
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document.write( "S = B-1\r\n" );
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document.write( "We have the equations:\r\n" );
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document.write( "F+M+S+B = 100\r\n" );
document.write( "F² = M²+S²+B²\r\n" );
document.write( "S = B-1\r\n" );
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document.write( "Substitute B-1 for S in the first two:\r\n" );
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document.write( "F+M+B-1+B = 100\r\n" );
document.write( "F² = M²+(B-1)²+B²\r\n" );
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document.write( "Simplify the first:\r\n" );
document.write( "F+M+2B = 101\r\n" );
document.write( "F = 101-M-2B\r\n" );
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document.write( "Simplify the second:\r\n" );
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document.write( "F² = M²+S²+(B-1)²\r\n" );
document.write( "F² = M²+B²-2B+1+B²\r\n" );
document.write( "F² = M²+2B²-2B+1\r\n" );
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document.write( "Substitute 101-M-2B for F\r\n" );
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document.write( "(101-M-2B)² = M²+2B²-2B+1\r\n" );
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document.write( "Simplify\r\n" );
document.write( "4B^2+4BM-404B+M^2-202M+10201 = M²+2B²-2B+1\r\n" );
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document.write( "10201+M^2+4B^2-202M-404B+4BM = M²+2B²-2B+1\r\n" );
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document.write( "2B^2+4BM-402B-202M+10200 = 0\r\n" );
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document.write( "Solve that for M:\r\n" );
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document.write( "4BM-202M = 2B^2-402B+10200 \r\n" );
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document.write( "Divide through by 2\r\n" );
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document.write( "2BM-101M = B^2-201B+5100\r\n" );
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document.write( "Factor out M on the left\r\n" );
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document.write( "M(2B-100) = B^2-201B+5100\r\n" );
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document.write( "\"M=%28B%5E2-201B%2B5100%29%2F%28101-2B%29\"\r\n" );
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document.write( "Now with your TI-83 or 84 calculator, put\r\n" );
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document.write( "\"%28x%5E2-201x%2B5100%29%2F%28101-2x%29\"  as Y1\r\n" );
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document.write( "Press 2ND WINDOW (for TBLST)\r\n" );
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document.write( "Set TblStart=0 and ΔTbl=1 highlight Auto both places\r\n" );
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document.write( "Press 2ND GRAPH (for TABLE)\r\n" );
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document.write( "Using the down arrow key, scroll down the X column until \r\n" );
document.write( "you find a whole number under the Y1 column.\r\n" );
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document.write( "You find that when you get to 14 under the column X,\r\n" );
document.write( "where you read 34 under Y1.\r\n" );
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document.write( "So that means that B=14 and M=34\r\n" );
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document.write( "Substitute that in F = 101-M-2B\r\n" );
document.write( "                   F = 101-34-2(14) \r\n" );
document.write( "                   F = 39\r\n" );
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document.write( "Then substitute B=14 in S = B-1\r\n" );
document.write( "                        S = 14-1\r\n" );
document.write( "                        S = 13\r\n" );
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document.write( "So the father is 39, the mother is 34,\r\n" );
document.write( "the brother is 14, and the sister is 13.\r\n" );
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document.write( "Edwin
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