Help solving an exponential equation 
Help solving an exponential equation 
neuro.akn 
May 08, 2013, 10:59 AM
Post
#1

Newbie Group: Basic Member Posts: 23 Joined: Dec 21, 2012 Member No.: 34766 
Hello, I have an exponential equation with which I am experiencing some difficulty. If someone could help, it would be greatly appreciated. Thanks in advance. The problem is:
2^x+1 + 3(2^x) = 81. Solve for x. 
Dave C 
May 13, 2013, 02:55 AM
Post
#2

Newbie Group: Basic Member Posts: 22 Joined: Feb 01, 2013 Member No.: 34869 
2^x+1 + 3(2^x) = 81 Solving for x.
2^x+3(2^x)=80 subtracting 1 from both sides 4(2^x)=80 adding 2^x's together 2^x=20 dividing both sides by 4 x=approximately 4.3219281 not a very clean question a better question is perhaps: 2^x+1 + 3(2^x) = 65 where x=4 exactly I hope this helps Dave C. 
P JayS 
Jun 18, 2013, 10:03 PM
Post
#3

DemiGod Group: Basic Member Posts: 588 Joined: Apr 04, 2012 Member No.: 34146 
Hello, I have an exponential equation with which I am experiencing some difficulty. If someone could help, it would be greatly appreciated. Thanks in advance. The problem is: 2^x+1 + 3(2^x) = 81. Solve for x. x=4 2^x+1 = 2^5 + 3(2^4) = 32 + 48 = 80 80 + 1 = 81 P.j.S 
Dave C 
Sep 03, 2013, 07:13 AM
Post
#4

Newbie Group: Basic Member Posts: 22 Joined: Feb 01, 2013 Member No.: 34869 
2^x+1 + 3(2^x) = 81. Solve for x. x=4 2^x+1 = 2^5 + 3(2^4) = 32 + 48 = 80 80 + 1 = 81 P.j.S I see how the equation could be interpreted as 2^(x+1) + 3(2^x) = 81 Unfortunately it is still not a clean equation since you added the 1 twice as (x+1) and 80+1. Even using your interpretation a better equation would be 2^(x+1) + 3(2^x) = 80 not 81 Usually when an equation is not “clean” it is because the equation itself has not been copied correctly, and I suspect this is the case here. Dave C. 
neuro.akn 
Sep 10, 2013, 12:48 PM
Post
#5

Newbie Group: Basic Member Posts: 23 Joined: Dec 21, 2012 Member No.: 34766 
Thank you for your help.

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