document.write( "Question 124955: Please help I am getting confused...I need to solve each system by the substitution method. \r
\n" ); document.write( "\n" ); document.write( "\"x%2B3y=2\" first
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Algebra.Com's Answer #91602 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%2B3y=2%2C-x%2By=1%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%2B3y=2\" Start with the first equation\r
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\n" ); document.write( "\n" ); document.write( "\"3y=2-x\" Subtract \"x\" from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"3y=-x%2B2\" Rearrange the equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-x%2B2%29%2F%283%29\" Divide both sides by \"3\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28%28-1%29%2F%283%29%29x%2B%282%29%2F%283%29\" Break up the fraction\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-1%2F3%29x%2B2%2F3\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "Since \"y=%28-1%2F3%29x%2B2%2F3\", we can now replace each \"y\" in the second equation with \"%28-1%2F3%29x%2B2%2F3\" to solve for \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"-x%2Bhighlight%28%28%28-1%2F3%29x%2B2%2F3%29%29=1\" Plug in \"y=%28-1%2F3%29x%2B2%2F3\" into the first equation. In other words, replace each \"y\" with \"%28-1%2F3%29x%2B2%2F3\". 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( "\"%283%29%28-1x-%281%2F3%29x%2B2%2F3%29=%283%29%281%29\" Multiply both sides by the LCM of 3. This will eliminate the fractions (note: if you need help with finding the LCM, check out this solver)\r
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\n" ); document.write( "\n" ); document.write( "\"-3x-1x%2B2=3\" Distribute and multiply the LCM to each side\r
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\n" ); document.write( "\n" ); document.write( "\"-4x%2B2=3\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"-4x=3-2\"Subtract 2 from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"-4x=1\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"x=%281%29%2F%28-4%29\" Divide both sides by -4 to isolate x\r
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\n" ); document.write( "\n" ); document.write( "\"x=-1%2F4\" Reduce\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=-1%2F4\"\r
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\n" ); document.write( "\n" ); document.write( "Since we know that \"x=-1%2F4\" we can plug it into the equation \"y=%28-1%2F3%29x%2B2%2F3\" (remember we previously solved for \"y\" in the first equation).\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-1%2F3%29x%2B2%2F3\" Start with the equation where \"y\" was previously isolated.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-1%2F3%29%28-1%2F4%29%2B2%2F3\" Plug in \"x=-1%2F4\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=1%2F12%2B2%2F3\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=3%2F4\" Combine like terms and reduce. (note: if you need help with fractions, check out this solver)\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=3%2F4\"\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=-1%2F4\" and \"y=3%2F4\"\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( "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%2B3y=2\" (red) and \"-x%2By=1\" (green) and the intersection of the lines (blue circle).\r
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