document.write( "Question 199078: 1. Joe has a collection of nickels and dimes that is worth $6.05. If the number of dimes was doubled and the number of nickels was decreased by 10, the value of the coins would be $9.85. How many dimes does he have?\r
\n" ); document.write( "\n" ); document.write( "I have no idea where to start with this the best I can do is to subtract 6.05 from 9.85 but I don't know how to find the answer to this problem. I do have to show my work but I am confused.
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Algebra.Com's Answer #149534 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Let n=number of nickels and d=number of dimes\r
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\n" ); document.write( "\n" ); document.write( "Since \"Joe has a collection of nickels and dimes worth $6.05\", this tells that \"0.05n%2B0.10d=6.05\". Multiply EVERY term by 100 (to make every number whole) to get \"5n%2B10d=605\"\r
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\n" ); document.write( "\n" ); document.write( "So the first equation is \"5n%2B10d=605\"\r
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\n" ); document.write( "\n" ); document.write( "Also, \"the number of dimes was doubled and the number of nickels was decreased by 10, the value would be $9.85\" means that \"0.05%28n-10%29%2B0.10%282d%29=9.85\". Distribute to get \"0.05n-0.5%2B0.2d=9.85\". Multiply EVERY term by 100 to make every number positive. So we now get \"5n-50%2B20d=985\". Add 50 to both sides to get \"5n%2B20d=1035\"\r
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\n" ); document.write( "\n" ); document.write( "So the second equation is \"5n%2B20d=1035\"\r
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\n" ); document.write( "\n" ); document.write( "So we have the system of equations:\r
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\n" ); document.write( "\n" ); document.write( "\"system%285n%2B10d=605%2C5n%2B20d=1035%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"-1%285n%2B10d%29=-1%28605%29\" Multiply the both sides of the first equation by -1.\r
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\n" ); document.write( "\n" ); document.write( "\"-5n-10d=-605\" Distribute and multiply.\r
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\n" ); document.write( "\n" ); document.write( "So we have the new system of equations:\r
\n" ); document.write( "\n" ); document.write( "\"system%28-5n-10d=-605%2C5n%2B20d=1035%29\"\r
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\n" ); document.write( "\n" ); document.write( "Now add the equations together. You can do this by simply adding the two left sides and the two right sides separately like this:\r
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\n" ); document.write( "\n" ); document.write( "\"%28-5n-10d%29%2B%285n%2B20d%29=%28-605%29%2B%281035%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28-5n%2B5n%29%2B%28-10d%2B20d%29=-605%2B1035\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0n%2B10d=430\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"10d=430\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"d=%28430%29%2F%2810%29\" Divide both sides by \"10\" to isolate \"d\".\r
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\n" ); document.write( "\n" ); document.write( "\"d=43\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"-5n-10d=-605\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-5n-10%2843%29=-605\" Plug in \"d=43\".\r
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\n" ); document.write( "\n" ); document.write( "\"-5n-430=-605\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"-5n=-605%2B430\" Add \"430\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"-5n=-175\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"n=%28-175%29%2F%28-5%29\" Divide both sides by \"-5\" to isolate \"n\".\r
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\n" ); document.write( "\n" ); document.write( "\"n=35\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So our answers are \"n=35\" and \"d=43\".\r
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\n" ); document.write( "\n" ); document.write( "This means that there are 35 nickels and 43 dimes
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