document.write( "Question 124486: 1000x+30y=500
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Algebra.Com's Answer #91233 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%281000x%2B30y=500%2Cx-2y=11%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( "\"1000x%2B30y=500\" Start with the first equation\r
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\n" ); document.write( "\n" ); document.write( "\"30y=500-1000x\" Subtract \"1000x\" from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"30y=-1000x%2B500\" Rearrange the equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-1000x%2B500%29%2F%2830%29\" Divide both sides by \"30\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28%28-1000%29%2F%2830%29%29x%2B%28500%29%2F%2830%29\" Break up the fraction\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-100%2F3%29x%2B50%2F3\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "Since \"y=%28-100%2F3%29x%2B50%2F3\", we can now replace each \"y\" in the second equation with \"%28-100%2F3%29x%2B50%2F3\" to solve for \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"x-2highlight%28%28%28-100%2F3%29x%2B50%2F3%29%29=11\" Plug in \"y=%28-100%2F3%29x%2B50%2F3\" into the first equation. In other words, replace each \"y\" with \"%28-100%2F3%29x%2B50%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( "\"x%2B%28-2%29%28-100%2F3%29x%2B%28-2%29%2850%2F3%29=11\" Distribute \"-2\" to \"%28-100%2F3%29x%2B50%2F3\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B%28200%2F3%29x-100%2F3=11\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"%283%29%281x%2B%28200%2F3%29x-100%2F3%29=%283%29%2811%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%2B200x-100=33\" Distribute and multiply the LCM to each side\r
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\n" ); document.write( "\n" ); document.write( "\"203x-100=33\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"203x=33%2B100\"Add 100 to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"203x=133\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28133%29%2F%28203%29\" Divide both sides by 203 to isolate x\r
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\n" ); document.write( "\n" ); document.write( "\"x=19%2F29\" 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=19%2F29\"\r
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\n" ); document.write( "\n" ); document.write( "Since we know that \"x=19%2F29\" we can plug it into the equation \"y=%28-100%2F3%29x%2B50%2F3\" (remember we previously solved for \"y\" in the first equation).\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-100%2F3%29x%2B50%2F3\" Start with the equation where \"y\" was previously isolated.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-100%2F3%29%2819%2F29%29%2B50%2F3\" Plug in \"x=19%2F29\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=-1900%2F87%2B50%2F3\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=-150%2F29\" 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=-150%2F29\"\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=19%2F29\" and \"y=-150%2F29\"\r
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\n" ); document.write( "\n" ); document.write( "which form the point \r
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