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        riddles >> easy >> 3^x
        
(Message started by: codpro880 on Feb 25th, 2009, 5:17pm)
Title: 3^x
Post by codpro880 on Feb 25th, 2009, 5:17pm
Find the value of x without using a calculator/logarithms:

3^x-3^(x-1)=162
Title: Re: 3^x
Post by howard roark on Feb 25th, 2009, 5:41pm
[hide]5?[/hide]
Title: Re: 3^x
Post by codpro880 on Feb 25th, 2009, 6:15pm
Yes, but show the algebra :)
Title: Re: 3^x
Post by howard roark on Feb 25th, 2009, 7:46pm
[hide]3^x-3^x/3=162

(2/3)3^x=162

3^x=243

x=5[/hide]
Title: Re: 3^x
Post by rmsgrey on Feb 26th, 2009, 9:34am
[hide]162=200003
=1000003-100003
=103x-103x-1

x=5[/hide]


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