document.write( "Question 147492: y=x+1\r
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Algebra.Com's Answer #107863 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Start with the given system\r
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\n" ); document.write( "\n" ); document.write( "\"8x-4%28x%2B1%29=0\" Plug in \"y=x%2B1\" into the first equation. In other words, replace each \"y\" with \"x%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( "\"8x-4x-4=0\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"4x-4=0\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"4x=0%2B4\"Add 4 to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"4x=4\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"x=%284%29%2F%284%29\" Divide both sides by 4 to isolate x\r
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\n" ); document.write( "\n" ); document.write( "\"x=1\" Divide\r
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\n" ); document.write( "\n" ); document.write( "Now that we know that \"x=1\", we can plug this into \"y=x%2B1\" to find \"y\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=%281%29%2B1\" Substitute \"1\" for each \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=2\" Simplify\r
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\n" ); document.write( "\n" ); document.write( "So our answer is \"x=1\" and \"y=2\" 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+-8x%2F%28-4%29%2C+x%2B1%29+\" Graph of \"8x-4y=0\" (red) and \"y=x%2B1\" (green)\r
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