SOLUTION: 1. Find x; if 3^2x+5=3^2x+3+72 2.Evaluate (³√xy²÷x²y) for x= 27 and y=64 3. Find x; if 5^x-2×3

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: 1. Find x; if 3^2x+5=3^2x+3+72 2.Evaluate (³√xy²÷x²y) for x= 27 and y=64 3. Find x; if 5^x-2×3       Log On


   

Question 1082417: 1. Find x; if 3^2x+5=3^2x+3+72
2.Evaluate (³√xy²÷x²y) for x= 27 and y=64
3. Find x; if 5^x-2×3
Answer by ikleyn(52810) About Me  (Show Source):
You can put this solution on YOUR website!
.
1. Find x; if 3^2x+5=3^2x+3+72
~~~~~~~~~~~~~~~~~~

I applied all the power of my mind and guessed, finally, that it means
3^(2x+5) = 3^(2x+3) + 72.

NEXT TIME PLEASE USE PARENTHESES when post formulas to this site.
It is MANDATORY, otherwise your formulas are UNREADABLE ! 

3%5E%282x%2B5%29 = 3%5E%282x%2B3%29+%2B+72 

Introduce new variable y = 3%5E%282x%2B3%29.
Then your equation takes the form

9y = y + 72  --->  

8y = 72 ---

y = 72%2F8 = 9  --->

3%5E%282x%2B3%29 = 9  --->  2x+3 = 2  --->  2x = -1  ---> x = -1%2F2.


Answer.  x = -1%2F2.



2.  Regarding your #2, I simply can not read your writing.


3.  Find x; if 5^x-2×3       It is nonsence. I hope you do understand it.


There is THE RULE in this forum:

One problem per post and one question per post.