document.write( "Question 1155415: Hello, can someone please help me with this problem:
\n" ); document.write( "Use the properties of exponents to rewrite y=4e^{-0.5t} in the form y=a(1+r)^t or y=a(1-r)^t . Round the value of r to the nearest thousandth. Then find the percent rate of change to the nearest tenth of percent.
\n" ); document.write( "I really need to know what the percent rate of change is.
\n" ); document.write( "I have tried but I really just don't understand how to do it.
\n" ); document.write( "Please help, Thanks.
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Algebra.Com's Answer #777993 by MathLover1(20849)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "\"y=4e%5E%28-0.5t%29+\"\r
\n" ); document.write( "\n" ); document.write( " in the form \"y=a%281%2Br%29%5Et\" or\"+y=a%281-r%29%5Et+\"\r
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\n" ); document.write( "\n" ); document.write( "first you need to find \"r\" that makes following statement true\r
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\n" ); document.write( "\n" ); document.write( "\"e%5E%28-0.5t%29+=%281%2Br%29%5Et\".....take log of both sides\r
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\n" ); document.write( "\n" ); document.write( "\"log%28e%5E%28-0.5t%29+%29=log%28%281%2Br%29%5Et%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28-0.5t%29log%28e+%29=t%2Alog%28%281%2Br%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28-0.5cross%28t%29%29log%28e+%29%2Fcross%28t%29=log%28%281%2Br%29%29\"...write \"-0.5\" as \"-1%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28-1%2F2%29log%28e+%29=log%28%281%2Br%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"log%28e%5E%28-1%2F2%29+%29=log%28%281%2Br%29%29\".....apply exponent rule \"e%5E%28-1%2F2%29=1%2Fe%5E%281%2F2%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"log%281%2Fe%5E%281%2F2%29+%29=log%28%281%2Br%29%29\".......\"e%5E%281%2F2%29=sqrt%28e%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"log%281%2Fsqrt%28e%29+%29=log%28%281%2Br%29%29\".....if log same, we have\r
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\n" ); document.write( "\n" ); document.write( "\"1%2Fsqrt%28e%29+=1%2Br\"\r
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\n" ); document.write( "\n" ); document.write( "\"r+=+1%2Fsqrt%28e%29+-+1\"\r
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\n" ); document.write( "\n" ); document.write( "your equation in the form \"y=a%281%2Br%29%5Et\" is:
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\n" ); document.write( "\n" ); document.write( "\"a=4\", \"r+=+1%2Fsqrt%28e%29+-+1\"}\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"y=4%281%2B1%2Fsqrt%28e%29+-+1%29%5Et\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=4%281%2Fsqrt%28e%29+%29%5Et\"\r
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\n" ); document.write( "\n" ); document.write( "check:\r
\n" ); document.write( "\n" ); document.write( "\"+4e%5E%28-0.5t%29=4%281%2Fsqrt%28e%29+%29%5Et+\"-> true\r
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\n" ); document.write( "\n" ); document.write( "or \r
\n" ); document.write( "\n" ); document.write( "\"y=4%281-r%29%5Et\"\r
\n" ); document.write( "\n" ); document.write( "\"y=4%281-%281%2Fsqrt%28e%29+-+1%29%29%5Et\"\r
\n" ); document.write( "\n" ); document.write( "\"y=4%281-1%2Fsqrt%28e%29%2B+1%29%5Et\"\r
\n" ); document.write( "\n" ); document.write( "\"y=4%282-1%2Fsqrt%28e%29%29%5Et\"\r
\n" ); document.write( "\n" ); document.write( "check:\r
\n" ); document.write( "\n" ); document.write( "\"+4e%5E%28-0.5t%29=4%282-1%2Fsqrt%28e%29%29%5Et\"-> not true\r
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\n" ); document.write( "\n" ); document.write( "so, your answer is: \"y=4%281%2Fsqrt%28e%29+%29%5Et\"\r
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