document.write( "Question 923083: find the value of two numbers if their sum is 12 and their difference is 4 \n" ); document.write( "
Algebra.Com's Answer #559857 by MathLover1(20850)\"\" \"About 
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\n" ); document.write( "let's two numbers be \"x\" and \"y\"\r
\n" ); document.write( "\n" ); document.write( "if their sum is \"12\", we have\r
\n" ); document.write( "\n" ); document.write( "\"x%2By=12\"....eq.1\r
\n" ); document.write( "\n" ); document.write( " and their difference is \"4\"\r
\n" ); document.write( "\n" ); document.write( "\"x-y=4\"....eq.2\r
\n" ); document.write( "\n" ); document.write( "solve the system:\r
\n" ); document.write( "\n" ); document.write( "\"x%2By=12\"....eq.1
\n" ); document.write( "\"x-y=4\"....eq.2
\n" ); document.write( "_____________________add both\r
\n" ); document.write( "\n" ); document.write( "\"x%2Bcross%28y%29%2Bx-cross%28y%29=12%2B4\"\r
\n" ); document.write( "\n" ); document.write( "\"2x=16\"\r
\n" ); document.write( "\n" ); document.write( "\"x=16%2F2\"\r
\n" ); document.write( "\n" ); document.write( "\"highlight%28x=8%29\"\r
\n" ); document.write( "\n" ); document.write( "go to \"x%2By=12\"....eq.1 plug in \"x\"\r
\n" ); document.write( "\n" ); document.write( "\"8%2By=12\"\r
\n" ); document.write( "\n" ); document.write( "\"y=12-8\"\r
\n" ); document.write( "\n" ); document.write( "\"highlight%28y=4%29\"
\n" ); document.write( "
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