document.write( "Question 1090975: Please help me here.
\n" ); document.write( "Ax+By=C
\n" ); document.write( "Dx+Ey=F
\n" ); document.write( "Solve the system for x and y
\n" ); document.write( "I got x=C-By/A
\n" ); document.write( "y= (AF-CD)/(AE-BD)
\n" ); document.write( "Not sure if I am right.
\n" ); document.write( "Thank you.
\n" ); document.write( "

Algebra.Com's Answer #705414 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "You can use Cramer's Rule to solve this. Let's define the following\r
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  • P = the matrix \"%28matrix%282%2C2%2CA%2CB%2CD%2CE%29%29\" (notice it's the left hand side coefficients)

  • \n" ); document.write( "
  • Px = the matrix \"%28matrix%282%2C2%2CC%2CB%2CF%2CE%29%29\". I started with matrix P and I've replaced the first column with C and F, both of which are the right hand side values

  • \n" ); document.write( "
  • Py = the matrix \"%28matrix%282%2C2%2CA%2CC%2CD%2CF%29%29\". I started with matrix P ann replaced the second column with C and F, both of which are the right hand side values

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\r
\n" ); document.write( "\n" ); document.write( "The notation det(P) is the determinant of matrix P. Using the two-by-two matrix determinant rule we can say
\n" ); document.write( "\"det%28P%29+=+A%2AE+-+B%2AD\"
\n" ); document.write( "\"det%28Px%29+=+C%2AE+-+F%2AB\"
\n" ); document.write( "\"det%28Px%29+=+A%2AF+-+C%2AD\"\r
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\n" ); document.write( "\n" ); document.write( "Then you divide the determinants to get x and y\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28det%28Px%29%29%2F%28det%28P%29%29+=+%28C%2AE+-+F%2AB%29%2F%28A%2AE+-+B%2AD%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%28det%28Px%29%29%2F%28det%28P%29%29+=+%28A%2AF+-+C%2AD%29%2F%28A%2AE+-+B%2AD%29\"\r
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\n" ); document.write( "\n" ); document.write( "If we knew the values of A,B,C,D,E, and F, then we could compute the actual numeric values of x and y. However, since we don't know those six variables, we just leave it as shown above. \r
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\n" ); document.write( "\n" ); document.write( "So the final answers are
\n" ); document.write( "\"x+=+%28C%2AE+-+F%2AB%29%2F%28A%2AE+-+B%2AD%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%28A%2AF+-+C%2AD%29%2F%28A%2AE+-+B%2AD%29\"
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