How do i work out x ?

3 times 2 to the power of x-1 =24
i dont understand how to work out x

1 Answer
Jim G.
Aug 6, 2017

#x=4#

Explanation:

#"what we have is "#

#3xx2^(x-1)=24#

#"isolate "2^(x-1)" by dividing both sides by 3"#

#rArrcancel(3)^1/cancel(3)^1xx2^(x-1)=24/3#

#rArr2^(x-1)=8#

#• " note that "8=2^3#

#rArr2^(x-1)=2^3#

#"since the bases are both 2 we can equate the exponents"#

#rArrx-1=3#

#"adding 1 to both sides gives"#

#x=4#

#color(blue)"As a check"#

#3xx2^((4-1))=3xx2^3=3xx8=24larr" True"#

#rArrx=4" is the solution"#

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