A math related question, if a number is raised to a power of x how do you find x?

Question

The question i am stuck with is 3^x+1 = 15

Answer 1

You take the log base number of both sides.

3^x + 1 = 15
3^x = 14
x = log[base 3] 14

Then using the rule for the change of bases:
x = log(14) / log(3)

x ≈ 2.4021735

Double-checking:
3^(2.4021735) + 1 = 15

EDIT:

From your e-mail, you stated you meant to write this as:
3^(x+1) = 15

The method is the same.

Take the log [base 3] of both sides:

x + 1 = log[base 3] 15

The rule for the change of bases is:
log[ base b] x --> log(x) / log(b)

So this is the same as:
x + 1 = log(15) / log(3)

Now subtract 1 from both sides:
x = log(15) / log(3) - 1

Run this through your calculator and you should get:
x ≈ 1.46497352

Double-checking:
3^(2.46497352) = 15

Answer 2

use logarithm

first subtract 1 from both sides

3^x=14

log base 3 multiplied by 14=x