document.write( "Question 592940: I have been trying to find the answer to this equation for hours. It is a substitution method equation. Here it is, y=2x-3 x-y=-4. Please help! I have gotten multiple answers like x=1 and y=5 but my teacher says that isn't right and i also got x=4 and y=8 but that also isn't right. Please can you help me? \n" ); document.write( "
Algebra.Com's Answer #376135 by ankor@dixie-net.com(22740)![]() ![]() You can put this solution on YOUR website! y = 2x - 3 \n" ); document.write( " x - y = -4 \n" ); document.write( "Use the 1st equation for substitution, replace y with (2x-3) in the 2nd equation \n" ); document.write( "x - (2x-3) = -4 \n" ); document.write( "Removing the brackets changes the sign of 3 \n" ); document.write( "x - 2x + 3 = -4 \n" ); document.write( "-x = -4 - 3 \n" ); document.write( "-x = -7 \n" ); document.write( "Multiply both sides by -1 \n" ); document.write( "x = 7 \n" ); document.write( ": \n" ); document.write( "Find y using the 1st equation, replace x with 7 \n" ); document.write( "y = 2(7) - 3 \n" ); document.write( "y = 14 - 3 \n" ); document.write( "y = 11 \n" ); document.write( ": \n" ); document.write( ": \n" ); document.write( "Check these solution in the 2nd equation \n" ); document.write( "x - y = -4 \n" ); document.write( "7 - 11 = -4 \n" ); document.write( " |