5^(x+1)+5*2^(x-2)=104

Here's a numerical approach:

x ≈ 1.858042273

.

This would be a difficult one to solve, algebraically.....here's a graph of the solution......

https://www.desmos.com/calculator/ry6ssblibf

Desmos gives the solution as x = 1.858  [approximately]

[Thanks, Alan, for spotting my earlier mistake in typing in the incorrect function.......!!!! ]

CONTINUED  HERE

http://web2.0calc.com/questions/5-x-1-5-2-x-2-104-x-5

ANON - PLEASE DO NOT ASKE QUESTIONS TWICE LIKE THIS.

IT CAUSES CONFUSION AND WASTES ANSWERERS TIME.

IF YOUR QUESTION HAS FALLEN OFF THE FIRST PAGE (or even just a fair way back in the queue) THEN YOU CAN MAKE A NEW POST  THAT GIVES THE ADDRESS OF THE OLD POST!

Most times you will get an answer quickly if you do this. :)