document.write( "Question 1088599: 3^-3x = 81\r
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document.write( "I started here by taking the log of both sides to solve for x. My final answer ended up 4/-3, or -1.333. This was marked wrong. Any insight? \n" );
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Algebra.Com's Answer #702877 by addingup(3677) You can put this solution on YOUR website! 3^(-3x) = 81 \n" ); document.write( "log(3^(-3x)) = log(81) \n" ); document.write( "Since the logarithm of a number raised to a power is the power times the logarithm of the number: \n" ); document.write( "((-3)x)(log(3)) = log(81) \n" ); document.write( "(-3)x = log(81)/log(3) \n" ); document.write( "(-3)x = log_3(81) = 4 \n" ); document.write( "x = 4/-3 = -1.3333 \n" ); document.write( "Well, I'm afraid I haven't been of any help since I got the same answer you got and obviously your teacher is looking for a different answer. But I have solved the problem correctly, so whoever is telling you that this is the wrong answer is, in my view, making a mistake. S/he needs to work the problem so s/he can see that the answer book they have is incorrect. Good luck.\r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |