document.write( "Question 152569: How many solutions are in the equation: (-2x+y=1, -4x+2y=-8) \n" ); document.write( "
Algebra.Com's Answer #112144 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\r
\n" ); document.write( "\n" ); document.write( "Start with the given system of equations:\r
\n" ); document.write( "\n" ); document.write( "\"system%28-2x%2By=1%2C-4x%2B2y=-8%29\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"-2%28-2x%2By%29=-2%281%29\" Multiply the both sides of the first equation by -2.\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"4x-2y=-2\" Distribute and multiply.\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "So we have the new system of equations:\r
\n" ); document.write( "\n" ); document.write( "\"system%284x-2y=-2%2C-4x%2B2y=-8%29\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Now add the equations together. You can do this by simply adding the two left sides and the two right sides separately like this:\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"%284x-2y%29%2B%28-4x%2B2y%29=%28-2%29%2B%28-8%29\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"%284x%2B-4x%29%2B%28-2y%2B2y%29=-2%2B-8\" Group like terms.\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"0x%2B0y=-10\" Combine like terms. Notice how the x terms cancel out.\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"0=-10\"Simplify.\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Since \"0=-10\" is never true, this means that there are no solutions. So the system is inconsistent.
\n" ); document.write( "
\n" ); document.write( "
\n" );