I need step by step on how 2^x=64.  I am confused.  And I do not wish to use a calculator.  I would like to know the steps so that I can do it on my own.

2 Answers

embizze's profile pic

embizze | High School Teacher | (Level 2) Educator Emeritus

Posted on

It is convenient that this problem has a whole number solution. In order to solve `2^x=64` without a calcultor you start listing the multiples of 2 and hope that 64 is one of them.







Thus x=6.

You don't indicate what level of math class you are in. If this is a college algebra class, you will need the methods referenced by etotheeyepi and elekzy -- namely logarithms and exponentials. If this is an algebra class, perhaps dealing with basic exponentials or sequences and series, you will be able to use a guess and check strategy without a calculator.

But solving `2^x=18` without a calculator would be a daunting task indeed.

**Note that both of the above answers assumed you knew the answer. They both used `64=2^6` before solving for x. The correct method using logarithms is:




`x=(ln64)/(ln2)=6` , but this requires a calculator or log tables.


etotheeyepi's profile pic

etotheeyepi | Student, Undergraduate | (Level 1) Valedictorian

Posted on

2^x = 64

x log 2 = log 64

if the log is base two you could write it like this

x log 2 = 6 log 2

x = 6