document.write( "Question 259892: use natural log to solve: 9*2^z=19*11^z solve for z \n" ); document.write( "

Algebra.Com's Answer #191364 by ankor@dixie-net.com(22740) $\"\"$ $\"About$

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9*2^z = 19 * 11^z solve for z
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\n" ); document.write( "ln(9) + ln(2^z) = ln(19) + ln(11^z)
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\n" ); document.write( "2.197 + z*ln(2) = 2.944 + z*ln(11)
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\n" ); document.write( "2.197 + .693z = 2.944 + 2.398z
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\n" ); document.write( "2.197 - 2.944 = 2.398z - .693z
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\n" ); document.write( "-.747 = 1.705z
\n" ); document.write( "z = $\"%28-.747%29%2F1.705\"$
\n" ); document.write( "z = -.438
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\n" ); document.write( "Check on a calc: enter:
\n" ); document.write( " 9 * 2^-.438 = 6.643
\n" ); document.write( "and
\n" ); document.write( " 19 * 11^-.438 = 6.646, close enough \n" ); document.write( "

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