Question 61910
The given expression is: 

16^(2 - 5x) = 64^(x + 4) 


16 can be written as 4^2 and 64 can be written as 4^3.


Hence, the above expression becomes:


4<sup>2(2 - 5x)</sup> = 4<sup>3(x + 4)</sup> 


Since, the bases are same, we equate the powers.


2(2 - 5x) = 3(x + 4) 



4 - 10x = 3x + 12 


0 = 8 + 13x


13x = - 8 


x = {{{-8/13}}}


Hence, the solution.