document.write( "Question 422738: I am trying to write equations to represent two phone plans. One plan is $20 with 30 minutes free and .10 for each additional minute. The second plan is $51 with 100 minutes free and .o4 for each additional minute. Then how can I compare the costs? \n" ); document.write( "
Algebra.Com's Answer #295057 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
Write a cost equation for each statement:
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\n" ); document.write( "Let m = no. of minutes used (greater than 100 min)
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\n" ); document.write( "One plan is $20 with 30 minutes free and .10 for each additional minute.
\n" ); document.write( "C = .10(m-30) + 20
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\n" ); document.write( "The second plan is $51 with 100 minutes free and .o4 for each additional minute.
\n" ); document.write( "C = .04(m-100) + 51
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\n" ); document.write( "Then how can I compare the costs?
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\n" ); document.write( "How many minutes will you have to use to make the 1st plan more expensive than the 2nd plan?
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\n" ); document.write( " 1st plan cost more than 2nd plan
\n" ); document.write( " .10(m-30) + 20 > .04(m-100) + 51
\n" ); document.write( " .10m - 3 + 20 > .04m - 4 + 51
\n" ); document.write( " .10m + 17 > .04m + 47
\n" ); document.write( " .10m - .04m > 47 - 17
\n" ); document.write( ".06m > 30
\n" ); document.write( "m > \"30%2F.06\"
\n" ); document.write( "m > 500 minutes use, will make the 2nd plan a better deal
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\n" ); document.write( "Check this for yourself, assume m = 501 min
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\n" ); document.write( "did this make sense to you?
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