document.write( "Question 126655This question is from textbook Beginning Algebra
\n" ); document.write( ": x+5y=10
\n" ); document.write( "-2x-10y=-20\r
\n" ); document.write( "\n" ); document.write( "5y=x+10
\n" ); document.write( "divide by 5, each side
\n" ); document.write( "y=x+10/5
\n" ); document.write( "y=x/5+10/5
\n" ); document.write( "Problem with LCM
\n" ); document.write( "I then plug y into next equation
\n" ); document.write( "-2x-10(y equation)+ -10 (y equation)=-20
\n" ); document.write( "Need help to make sense out of LCM to finish problem
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Algebra.Com's Answer #92810 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%2B5y=10%2C-2x-10y=-20%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%2B5y=10\" Start with the first equation\r
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\n" ); document.write( "\n" ); document.write( "\"5y=10-x\" Subtract \"x\" from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"5y=-x%2B10\" Rearrange the equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-x%2B10%29%2F%285%29\" Divide both sides by \"5\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28%28-1%29%2F%285%29%29x%2B%2810%29%2F%285%29\" Break up the fraction\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-1%2F5%29x%2B2\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "Since \"y=%28-1%2F5%29x%2B2\", we can now replace each \"y\" in the second equation with \"%28-1%2F5%29x%2B2\" to solve for \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"-2x-10highlight%28%28%28-1%2F5%29x%2B2%29%29=-20\" Plug in \"y=%28-1%2F5%29x%2B2\" into the first equation. In other words, replace each \"y\" with \"%28-1%2F5%29x%2B2\". 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( "\"-2x%2B%28-10%29%28-1%2F5%29x%2B%28-10%29%282%29=-20\" Distribute \"-10\" to \"%28-1%2F5%29x%2B2\"\r
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\n" ); document.write( "\n" ); document.write( "\"-2x%2B%2810%2F5%29x-20=-20\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"%285%29%28-2x%2B%2810%2F5%29x-20%29=%285%29%28-20%29\" Multiply both sides by the LCM of 5. 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( "\"-10x%2B10x-100=-100\" Distribute and multiply the LCM to each side\r
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\n" ); document.write( "\n" ); document.write( "\"-100=-100\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"0=-100%2B100\"Add 100 to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"0=0\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "Since this equation is always true for any x value, this means x can equal any number. So there are an infinite number of solutions.\r
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