document.write( "Question 183044: Solve the equations for x and y or state that
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\n" ); document.write( "\n" ); document.write( "3x + 7y = 5
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Algebra.Com's Answer #137413 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%283x%2B7y=5%2C2x-y=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 second equation\r
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\n" ); document.write( "\n" ); document.write( "\"2x-y=1\" Start with the second equation\r
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\n" ); document.write( "\n" ); document.write( "\"-y=1-2x\" Subtract \"2x\" from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"-y=-2x%2B1\" Rearrange the equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-2x%2B1%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%281%29%2F%28-1%29\" Break up the fraction\r
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\n" ); document.write( "\n" ); document.write( "\"y=2x-1\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "Since \"y=2x-1\", we can now replace each \"y\" in the first equation with \"2x-1\" to solve for \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"3x%2B7highlight%28%282x-1%29%29=5\" Plug in \"y=2x-1\" into the first equation. In other words, replace each \"y\" with \"2x-1\". 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%287%29%282%29x%2B%287%29%28-1%29=5\" Distribute \"7\" to \"2x-1\"\r
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\n" ); document.write( "\n" ); document.write( "\"3x%2B14x-7=5\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"17x-7=5\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"17x=5%2B7\"Add 7 to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"17x=12\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"x=%2812%29%2F%2817%29\" Divide both sides by 17 to isolate x\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=12%2F17\"\r
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\n" ); document.write( "\n" ); document.write( "Since we know that \"x=12%2F17\" we can plug it into the equation \"y=2x-1\" (remember we previously solved for \"y\" in the first equation).\r
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\n" ); document.write( "\n" ); document.write( "\"y=2x-1\" Start with the equation where \"y\" was previously isolated.\r
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\n" ); document.write( "\n" ); document.write( "\"y=2%2812%2F17%29-1\" Plug in \"x=12%2F17\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=24%2F17-1\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=7%2F17\" Combine like terms (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=7%2F17\"\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=12%2F17\" and \"y=7%2F17\"\r
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\n" ); document.write( "\n" ); document.write( "which form the ordered pair \r
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