document.write( "Question 169624: Solve each system by substitution. Determine whether the equations are independent, dependent or inconsistent:
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Algebra.Com's Answer #125007 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "Start with the given system of equations:\r
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\n" ); document.write( "\n" ); document.write( "\"system%282x-y=4%2C2x-y=3%29\"\r
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\n" ); document.write( "\n" ); document.write( "Now in order to solve this system by using substitution, we need to solve (or isolate) one variable. I'm going to solve for y.\r
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\n" ); document.write( "\n" ); document.write( "So let's isolate y in the first equation\r
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\n" ); document.write( "\n" ); document.write( "\"2x-y=4\" Start with the first equation\r
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\n" ); document.write( "\n" ); document.write( "\"-y=4-2x\" Subtract \"2x\" from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"-y=-2x%2B4\" Rearrange the equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-2x%2B4%29%2F%28-1%29\" Divide both sides by \"-1\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28%28-2%29%2F%28-1%29%29x%2B%284%29%2F%28-1%29\" Break up the fraction\r
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\n" ); document.write( "\n" ); document.write( "\"y=2x-4\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "Since \"y=2x-4\", we can now replace each \"y\" in the second equation with \"2x-4\" to solve for \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"2x-highlight%28%282x-4%29%29=3\" Plug in \"y=2x-4\" into the second 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( "\"2x-2x%2B4=3\" Distribute the negative\r
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\n" ); document.write( "\n" ); document.write( "\"4=3\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"0=3-4\"Subtract 4 from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"0=-1\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "Since this equation is NEVER true for any x value, this means there are no solutions.\r
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\n" ); document.write( "\n" ); document.write( "So the system is inconsistent
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