document.write( "Question 126656This question is from textbook Beginning Algebra
\n" ); document.write( ": 8x-4y=16
\n" ); document.write( " y=2x-4
\n" ); document.write( "Solve by substition\r
\n" ); document.write( "\n" ); document.write( "4y=8x-16
\n" ); document.write( "divide both sides by 4y
\n" ); document.write( "y=8x-16/4
\n" ); document.write( "y=8x/4+16/4
\n" ); document.write( "y=4x/2+16/4
\n" ); document.write( "reduce
\n" ); document.write( "y=2x+4\r
\n" ); document.write( "\n" ); document.write( "Upon plugging top equation of y into bottom equation, I became confused I came up with
\n" ); document.write( "y=2x-4 and y=2x+4
\n" ); document.write( "I must have done something wrong along the line\r
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Algebra.Com's Answer #92809 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Start with the given system\r
\n" ); document.write( "\n" ); document.write( "\"8x-4y=16\"
\n" ); document.write( "\"y=2x-4\"\r
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\n" ); document.write( "\n" ); document.write( "\"8x-4%282x-4%29=16\" Plug in \"y=2x-4\" into the first equation. In other words, replace each \"y\" with \"2x-4\". Notice we've eliminated the \"y\" variables. So we now have a simple equation with one unknown.\r
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\n" ); document.write( "\n" ); document.write( "\"8x-8x%2B16=16\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"16=16\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"0=16-16\"Subtract 16 from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"0=0\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "Since this equation is always true for any x value, this means x can equal any number. So there are an infinite number of solutions.
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