
\n" );
document.write( "\r\n" );
document.write( "Substitution is the worst way to solve a system which\r\n" );
document.write( "does not have any letters with coefficient of 1 or -1.\r\n" );
document.write( "Such systems are much easier solved by elimination.\r\n" );
document.write( "\r\n" );
document.write( "However, since you specified to do it by substitution,\r\n" );
document.write( "I will do so, but it will be much more difficult, as\r\n" );
document.write( "it will involve lots of work with fractions. Here goes:\r\n" );
document.write( "\r\n" );
document.write( "Solve the first equation for x\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "
\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "Substitute
for
\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "Cancel the 2 into the 4 and get a 2 where the 4 is\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "Distribute to remove the parentheses:\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "Combine like terms:\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "Add -10 to both sides:\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "Divide both sides by
\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "Cancel the
's, and simplify the right side\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "Now we substitute
for
into\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "Cancel the 3 into the
\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "Simplify the compound fraction by multiplying\r\n" );
document.write( "the numerator and denominator by the LCD of 5\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "Distribute the 5 into the parentheses, and write 10 for the\r\n" );
document.write( "denominator
:\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "Write 25 for 5*5 and cancel the 5's in the second\r\n" );
document.write( "term on top:\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "We reduce the fraction:\r\n" );
document.write( "\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "So the solution is
,
\r\n" );
document.write( "\r\n" );
document.write( "But that is by far the hardest way to solve a \r\n" );
document.write( "system of equations which has none of the terms\r\n" );
document.write( "x, -x, y, or -y. The easist way would be the\r\n" );
document.write( "elimination method. \r\n" );
document.write( "\r\n" );
document.write( "Edwin
\r
\n" );
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document.write( "
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document.write( "
\n" );
document.write( "
\n" );
document.write( "\n" );
document.write( "
\n" );
document.write( " \n" );
document.write( "