document.write( "Question 242972: x varies inversely with y. When x is 40, y is 50. What is y when x is 25? \n" ); document.write( "
Algebra.Com's Answer #177981 by Edwin McCravy(20055)\"\" \"About 
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x varies inversely with y.
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document.write( "That says  \"x=k%2Fy\"\r\n" );
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\n" ); document.write( "When x is 40, y is 50.
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document.write( "With that information we can determine k:\r\n" );
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document.write( "\"x=k%2Fy\"\r\n" );
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document.write( "\"40=k%2F50\"\r\n" );
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document.write( "Multiply both sides by 50\r\n" );
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document.write( "\"50%2A40=50%2A%28k%2F50%29\"\r\n" );
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document.write( "\"2000=k\"\r\n" );
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document.write( "Now we must substitute that value \r\n" );
document.write( "of k into \"x=k%2Fy\"\r\n" );
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document.write( "Now we have the complete equation.\r\n" );
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document.write( "\"x=2000%2Fy\"\r\n" );
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document.write( "Now with that complete equation we can answer\r\n" );
document.write( "the other part:\r\n" );
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\n" ); document.write( "What is y when x is 25?
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document.write( "\"x=2000%2Fy\"\r\n" );
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document.write( "Substitute 25 for x\r\n" );
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document.write( "\"25=2000%2Fy\"\r\n" );
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document.write( "Multiply both sides by y\r\n" );
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document.write( "\"y%2825%29=y%282000%2Fy%29\"\r\n" );
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document.write( "\"25y+=+2000\"\r\n" );
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document.write( "\"y=2000%2F25\"\r\n" );
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document.write( "\"y=80\"\r\n" );
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document.write( "Edwin
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