document.write( "Question 181876: I have tried this but I am having trouble, can you please help. Use substitution to solve each system. If it does not have one solution then put no solution or indinitely many solutions. X-5Y=36 2X+Y=-16 \n" ); document.write( "
Algebra.Com's Answer #136492 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-5y=36%2C2x%2By=-16%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%2By=-16\" Start with the second equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=-16-2x\" Subtract \"2x\" from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"y=-2x-16\" Rearrange the equation\r
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\n" ); document.write( "\n" ); document.write( "Since \"y=-2x-16\", we can now replace each \"y\" in the second equation with \"-2x-16\" to solve for \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"x-5highlight%28%28-2x-16%29%29=36\" Plug in \"y=-2x-16\" into the first equation. In other words, replace each \"y\" with \"-2x-16\". 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( "\"x%2B%28-5%29%28-2%29x%2B%28-5%29%28-16%29=36\" Distribute \"-5\" to \"-2x-16\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B10x%2B80=36\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"11x%2B80=36\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"11x=36-80\"Subtract 80 from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"11x=-44\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-44%29%2F%2811%29\" Divide both sides by 11 to isolate x\r
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\n" ); document.write( "\n" ); document.write( "\"x=-4\" 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=-4\"\r
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\n" ); document.write( "\n" ); document.write( "Since we know that \"x=-4\" we can plug it into the equation \"y=-2x-16\" (remember we previously solved for \"y\" in the first equation).\r
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\n" ); document.write( "\n" ); document.write( "\"y=-2x-16\" Start with the equation where \"y\" was previously isolated.\r
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\n" ); document.write( "\n" ); document.write( "\"y=-2%28-4%29-16\" Plug in \"x=-4\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=8-16\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=-8\" 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=-8\"\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=-4\" and \"y=-8\"\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-5y=36\" (red) and \"2x%2By=-16\" (green) and the intersection of the lines (blue circle).\r
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