document.write( "Question 246821: please help me to solve
\n" ); document.write( "2x-y=4
\n" ); document.write( "2x-y=3 by substitution \n" ); document.write( "
Algebra.Com's Answer #180149 by richwmiller(17219)\"\" \"About 
You can put this solution on YOUR website!
when we solve by substitution we solve one of the equations for x or y and then substitute that in the other equation
\n" ); document.write( "so if we solve 2x-y=4 for y, we will put the result in 2x-y=3 for y.
\n" ); document.write( "let's solve for y
\n" ); document.write( "2x-y=4
\n" ); document.write( "add y to both sides
\n" ); document.write( "2x=4+y
\n" ); document.write( "subtract 4 from both sides
\n" ); document.write( "2x-4=y
\n" ); document.write( "now substitute 2x-4 for y in 2x-1y=3
\n" ); document.write( "2x-1(2x-4)=3
\n" ); document.write( "Be careful of the signs
\n" ); document.write( "minus a plus is minus
\n" ); document.write( "but minus a minus is plus
\n" ); document.write( "if there is no sign it is a plus\r
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