document.write( "Question 331485: anyone but john please help with question. Solve the following ssystem of equation xy=1
\n" ); document.write( "2x-y=1 \n" ); document.write( "
Algebra.Com's Answer #237613 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
\r\n" );
document.write( "You don't need to use the quadratic formula,\r\n" );
document.write( "as the other tutor used, because it leads to \r\n" );
document.write( "a factorable quadratic:\r\n" );
document.write( "\r\n" );
document.write( "\"system%28xy=1%2C%0D%0A2x-y=1%29\"\r\n" );
document.write( "\r\n" );
document.write( "Solve the second equation for y:\r\n" );
document.write( "\r\n" );
document.write( "\"matrix%283%2C1%2C%0D%0A+++2x-y=1%2C%0D%0A+++2x-1=y%2C%0D%0A+++y=2x-1%0D%0A%29\" \r\n" );
document.write( "\r\n" );
document.write( "Substitute \"%282x-1%29\" in the first equation in the system\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "So there are two solutions for x.  We\r\n" );
document.write( "must find a value of y for each of them,\r\n" );
document.write( "by substituting each in \"y=2x-1\"\r\n" );
document.write( "\r\n" );
document.write( "Substituting \"x=-1%2F2\",\r\n" );
document.write( "\"y=2x-1\"\r\n" );
document.write( "\"y=2%28-1%2F2%29-1\"\r\n" );
document.write( "\"y=-1-1\"\r\n" );
document.write( "\"y=-2\"\r\n" );
document.write( "\r\n" );
document.write( "So one solution is (x,y) = (\"-1%2F2\",-2) \r\n" );
document.write( "\r\n" );
document.write( "Substituting \"x=1\",\r\n" );
document.write( "\"y=2x-1\"\r\n" );
document.write( "\"y=2%281%29-1\"\r\n" );
document.write( "\"y=2-1\"\r\n" );
document.write( "\"y=1\"\r\n" );
document.write( "\r\n" );
document.write( "So the other solution is (x,y) = (1,1)\r\n" );
document.write( "\r\n" );
document.write( "---------------------------\r\n" );
document.write( "\r\n" );
document.write( "Checking (x,y) = (\"-1%2F2\",-2)\r\n" );
document.write( "\r\n" );
document.write( "\"system%28xy=1%2C%0D%0A2x-y=1%29\"\r\n" );
document.write( "\r\n" );
document.write( "\"system%28%28-1%2F2%29%28-2%29=1%2C%0D%0A2%28-1%2F2%29-%28-2%29=1%29\"\r\n" );
document.write( "\r\n" );
document.write( "\"system%281=1%2C%0D%0A-1%2B2=1%29\"\r\n" );
document.write( "\r\n" );
document.write( "\"system%281=1%2C%0D%0A1=1%29\" \r\n" );
document.write( "\r\n" );
document.write( "Checking (x,y) = (1,1)\r\n" );
document.write( "\r\n" );
document.write( "\"system%28xy=1%2C%0D%0A2x-y=1%29\"\r\n" );
document.write( "\r\n" );
document.write( "\"system%28%281%29%281%29=1%2C%0D%0A2%281%29-%281%29=1%29\"\r\n" );
document.write( "\r\n" );
document.write( "\"system%281=1%2C%0D%0A2-1=1%29\"\r\n" );
document.write( "\r\n" );
document.write( "\"system%281=1%2C%0D%0A1=1%29\"\r\n" );
document.write( "\r\n" );
document.write( "Edwin
\n" ); document.write( "
\n" );