document.write( "Question 1101944: Solve by the elimination method.\r
\n" ); document.write( "\n" ); document.write( " 4a+9b=8
\n" ); document.write( " -4a+b=32\r
\n" ); document.write( "\n" ); document.write( "Determine the solution of the system. Select the correct choice below and, if necessary, fill in the answer box to complete your choice.\r
\n" ); document.write( "\n" ); document.write( "A.The solution is ? (type an ordered pair)
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\n" ); document.write( "B.There are infinitely many solutions.
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\n" ); document.write( "C.There is no solution.\r
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Algebra.Com's Answer #716581 by ikleyn(52781) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "Add the two equations. The terms \"4a\" and \"-4a\" will cancel each other, and you will get a single equation for one unknown \"b\" :\r\n" );
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document.write( "9b + b = 8 + 32,   or\r\n" );
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document.write( "10b = 40  ====>  b =  = 4.    (It is how the Elimination method works)\r\n" );
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document.write( "Then from the second of the two given equations you can determine \"a\":\r\n" );
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document.write( "-4a + 4 = 32  ====>  4a = 4 - 32  ====>  4a = -28  ====>  a =  = -7.\r\n" );
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document.write( "The given system has the unique solution, and this solution is   a= -7,  b= 4,  or  (a,b) = (-7,4).\r\n" );
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