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4 votes
Without using log, Solve for x.


25^(2x+3) =125^(2)

User Efel
by
5.4k points

2 Answers

3 votes

x=2.5

as

25squredx+3 so u take the power 3 to the other side then it will be

25squredx =125 to the power -1

squredx=125÷25

x=5÷2

x=2.5

User TheBlueNotebook
by
4.4k points
3 votes

Answer:
x=-6

Explanation:

Remember that:


a^x=a^y
x=y

The Power of a power property states that:


(a^m)^n=a^(mn)

Then, descompose 25 and 125 into their prime factors:


25=5*5=5^2\\125=5*5*5=5^3

Rewrite the expression:


(5^2)^(2x+3) =(5^3)^(x)

Then:


5^(4x+6) =5^(3x)\\4x+6=3x

Now, you can solve for x. Therefore you get that the result is


4x+6=3x\\4x-3x=-6\\x=-6

User Nitin Karale
by
5.4k points