
Mark H. answered 10/13/19
Tutoring in Math and Science at all levels
I assume you mean this:
log2 (4^x) = 16 (read the left side as "log to base 2 of 4^x")
The log of a number is the exponent applied to the base to get that number. Thus, the equivalent equation is:
2^16 = 4^x
2^16 = 4^8, so we have: 4^8 = 4^x, and therefore x = 8
CHECK:
log2 (4^8) = 8 * log24 = 8 * 2 = 16