document.write( "Question 142855: Solve by substitution or elimination and specify which method you did:
\n" ); document.write( "6x + 2y = 10
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\n" ); document.write( "\n" ); document.write( "(PS: Please show how you worked it out. I have been having mojor problems with these kinds of questions. Thanks.)
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Algebra.Com's Answer #103945 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%286x%2B2y=10%2C5x-3y=27%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( "\"6x%2B2y=10\" Start with the first equation\r
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\n" ); document.write( "\n" ); document.write( "\"2y=10-6x\" Subtract \"6x\" from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"2y=-6x%2B10\" Rearrange the equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-6x%2B10%29%2F%282%29\" Divide both sides by \"2\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28%28-6%29%2F%282%29%29x%2B%2810%29%2F%282%29\" Break up the fraction\r
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\n" ); document.write( "\n" ); document.write( "\"y=-3x%2B5\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "Since \"y=-3x%2B5\", we can now replace each \"y\" in the second equation with \"-3x%2B5\" to solve for \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"5x-3highlight%28%28-3x%2B5%29%29=27\" Plug in \"y=-3x%2B5\" into the first equation. In other words, replace each \"y\" with \"-3x%2B5\". 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( "\"5x%2B%28-3%29%28-3%29x%2B%28-3%29%285%29=27\" Distribute \"-3\" to \"-3x%2B5\"\r
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\n" ); document.write( "\n" ); document.write( "\"5x%2B9x-15=27\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"14x-15=27\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"14x=27%2B15\"Add 15 to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"14x=42\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"x=%2842%29%2F%2814%29\" Divide both sides by 14 to isolate x\r
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\n" ); document.write( "\n" ); document.write( "\"x=3\" Divide\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=-3x%2B5\" (remember we previously solved for \"y\" in the first equation).\r
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\n" ); document.write( "\n" ); document.write( "\"y=-3x%2B5\" Start with the equation where \"y\" was previously isolated.\r
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\n" ); document.write( "\n" ); document.write( "\"y=-3%283%29%2B5\" Plug in \"x=3\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=-9%2B5\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=-4\" 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=-4\"\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=-4\"\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 \"6x%2B2y=10\" (red) and \"5x-3y=27\" (green) and the intersection of the lines (blue circle).\r
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