SOLUTION: solve: 4(3^x )-108=0

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Question 1014248: solve:
4(3^x )-108=0

Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
4 * 3^x = 108 is where you start.

divide both sides of this equation by 4 to get 3^x = 108/4.

simplify to get 3^x = 27.

this is true if and only if x = 3, because 3^3 = 27.

you could also solve by logs.

take the log of both sides of this equation to get log(3^x) = log(27).

since log(3^x) = x*log(3), you get x * log(3) = log(27).

divide both sides of this equation by log(3) to get x = log(27)/log(3).

solve for x to get x = 3.

use the LOG function of your calculator to do this.