document.write( "Question 865184: HELP!!!!
\n" ); document.write( "9a+10b+12c=398
\n" ); document.write( "6a+4b+4c=164
\n" ); document.write( "1a+2b+1c=58
\n" ); document.write( "Solve for a,b,c and show work! \n" ); document.write( "
Algebra.Com's Answer #521626 by ankor@dixie-net.com(22740)\"\" \"About 
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9a + 10b + 12c = 398
\n" ); document.write( "6a + 4b + 4c = 164
\n" ); document.write( "1a + 2b + 1c = 58
\n" ); document.write( "Multiply the 1st equation by-1, the 3rd equations by 3
\n" ); document.write( "-9a - 10b - 12c = -398
\n" ); document.write( " 6a + 4b + 4c = 164
\n" ); document.write( " 3a + 6b + 3c = 174
\n" ); document.write( "---------------------Addition eliminates a & b, find c
\n" ); document.write( " 0a + 0b - 5c = -60
\n" ); document.write( "c = -60/-5
\n" ); document.write( "c = +12
\n" ); document.write( ":
\n" ); document.write( "using the 2nd and third equations replace c with 12
\n" ); document.write( "6a + 4b + 4(12) = 164
\n" ); document.write( "1a + 2b + 1(12) = 58
\n" ); document.write( ":
\n" ); document.write( "6a + 4b = 164 - 48
\n" ); document.write( "1a + 2b = 58 - 12
\n" ); document.write( ":
\n" ); document.write( "6a + 4b = 116
\n" ); document.write( "1a + 2b = 46
\n" ); document.write( "multiply the 2nd equation by -2
\n" ); document.write( " 6a + 4b = 116
\n" ); document.write( "-2a - 4b = -92
\n" ); document.write( "-----------------addition eliminates b, find a
\n" ); document.write( "4a = 24
\n" ); document.write( "a = 24/4
\n" ); document.write( "a = 6
\n" ); document.write( ":
\n" ); document.write( "Use the original 3rd equation to find b
\n" ); document.write( "1a + 2b + 1c = 58
\n" ); document.write( "6 + 2b + 12 = 58
\n" ); document.write( "2b = 58 - 18
\n" ); document.write( "2b = 40
\n" ); document.write( "b = 40/2
\n" ); document.write( "b = 20
\n" ); document.write( ":
\n" ); document.write( "You can confirm this for yourself in the 1st and 2nd equation \n" ); document.write( "
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