document.write( "Question 127515: y=2x+1
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Algebra.Com's Answer #93454 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "Start with the given system\r
\n" ); document.write( "\n" ); document.write( "\"y=2x%2B1\"
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\n" ); document.write( "\n" ); document.write( "\"3x%2B1=2x%2B1\" Plug in \"y=3x%2B1\" into the first equation. In other words, replace each \"y\" with \"3x%2B1\". 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( "\"3x=2x%2B1-1%29\"Subtract 1 from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"3x-2x=1-1\" Subtract 2x from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"-x=1-1\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"-x=0\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"x=%280%29%2F%28-1%29\" Divide both sides by -1 to isolate x\r
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\n" ); document.write( "\n" ); document.write( "\"x=0\" Divide\r
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\n" ); document.write( "\n" ); document.write( "Now that we know that \"x=0\", we can plug this into \"y=3x%2B1\" to find \"y\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=3%280%29%2B1\" Substitute \"0\" for each \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=1\" Simplify\r
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\n" ); document.write( "\n" ); document.write( "So our answer is \"x=0\" and \"y=1\" which also looks like \r
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\n" ); document.write( "\n" ); document.write( "Notice if we graph the two equations, we can see that their intersection is at . So this verifies our answer.\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28+500%2C+500%2C+-5%2C+5%2C+-5%2C+5%2C+2x%2B1%2C+3x%2B1%29+\" Graph of \"y=2x%2B1\" (red) and \"y=3x%2B1\" (green)\r
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