document.write( "Question 178917: can someone please help me with this problem I have to solve each system by addition \r
\n" ); document.write( "\n" ); document.write( "x+y=7
\n" ); document.write( "x-y=9 \n" ); document.write( "
Algebra.Com's Answer #133900 by colliefan(242)\"\" \"About 
You can put this solution on YOUR website!
x+y=7
\n" ); document.write( "x-y=9\r
\n" ); document.write( "\n" ); document.write( "You must combine these equations into one equation by adding each side together:
\n" ); document.write( "x+y=7
\n" ); document.write( "x-y=9
\n" ); document.write( "_________\r
\n" ); document.write( "\n" ); document.write( "x+y+x-y = 16\r
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\n" ); document.write( "\n" ); document.write( "Simplify:
\n" ); document.write( "2x=16
\n" ); document.write( "x=8\r
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\n" ); document.write( "\n" ); document.write( "Now, you have a solution for one of the variables, x. Substitute this value for x into either of the original equations to solve for y.
\n" ); document.write( "8+y=7
\n" ); document.write( "y=-1\r
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\n" ); document.write( "\n" ); document.write( "Now, you have the solution x=8m y=-1. Substitute these values in to the original equations to confirm that they solve them both. They do.\r
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