document.write( "Question 1065445: In the following equation, why multiply by -2 to solve the system for the y-value here on the first equation?\r
\n" ); document.write( "\n" ); document.write( "X+2y=7
\n" ); document.write( "2x+2y=13
\n" ); document.write( "

Algebra.Com's Answer #680603 by ikleyn(52778)\"\" \"About 
You can put this solution on YOUR website!
.
\n" ); document.write( "Multiply and then think.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "This is the KEY: to think.\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "The KEY is to THINK.\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "    The KEY is to THINK.\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "        The KEY is to THINK.\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "
\n" ); document.write( "
\n" );