document.write( "Question 143588: Solve system by the substitution method and indicate wheter each system is independent, inconsistent or dependent\r
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Algebra.Com's Answer #104501 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%28x-y=3%2C3x-2y=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( "\"x-y=3\" Start with the first equation\r
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\n" ); document.write( "\n" ); document.write( "\"-y=3-x\" Subtract \"x\" from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"-y=-x%2B3\" Rearrange the equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-x%2B3%29%2F%28-1%29\" Divide both sides by \"-1\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28%28-1%29%2F%28-1%29%29x%2B%283%29%2F%28-1%29\" Break up the fraction\r
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\n" ); document.write( "\n" ); document.write( "\"y=x-3\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "Since \"y=x-3\", we can now replace each \"y\" in the second equation with \"x-3\" to solve for \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"3x-2highlight%28%28x-3%29%29=3\" Plug in \"y=x-3\" into the first equation. In other words, replace each \"y\" with \"x-3\". 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%2B%28-2%29%281%29x%2B%28-2%29%28-3%29=3\" Distribute \"-2\" to \"x-3\"\r
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\n" ); document.write( "\n" ); document.write( "\"3x-2x%2B6=3\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B6=3\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"x=3-6\"Subtract 6 from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"x=-3\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "-----------------First Answer------------------------------\r
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\n" ); document.write( "\n" ); document.write( "So the first part of our answer is: \"x=-3\"\r
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\n" ); document.write( "\n" ); document.write( "Since we know that \"x=-3\" we can plug it into the equation \"y=x-3\" (remember we previously solved for \"y\" in the first equation).\r
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\n" ); document.write( "\n" ); document.write( "\"y=x-3\" Start with the equation where \"y\" was previously isolated.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-3%29-3\" Plug in \"x=-3\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=-3-3\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=-6\" Combine like terms \r
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\n" ); document.write( "\n" ); document.write( "-----------------Second Answer------------------------------\r
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\n" ); document.write( "\n" ); document.write( "So the second part of our answer is: \"y=-6\"\r
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\n" ); document.write( "\n" ); document.write( "-----------------Summary------------------------------\r
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\n" ); document.write( "\n" ); document.write( "So our answers are:\r
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\n" ); document.write( "\n" ); document.write( "\"x=-3\" and \"y=-6\"\r
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\n" ); document.write( "\n" ); document.write( "which form the point \r
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\n" ); document.write( "\n" ); document.write( "Since the system has a solution, this means that the system is independent and consistent.\r
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\n" ); document.write( "\n" ); document.write( "Now let's graph the two equations (if you need help with graphing, check out this solver)\r
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\n" ); document.write( "\n" ); document.write( "From the graph, we can see that the two equations intersect at . This visually verifies our answer.\r
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\n" ); document.write( "\n" ); document.write( " graph of \"x-y=3\" (red) and \"3x-2y=3\" (green) and the intersection of the lines (blue circle).\r
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