Answer: D.) 
Step-by-step explanation: We are given an exponential function f(x).
g(x) is an exponential function that is being reflected across y-axis.
According to rules of transformations y=f(-x).
That is variable x is being multiplied by a negative sign.
In the given options
, the variable x is being multiplied by a negative sign.
Therefore, correct option is D option.
50 - 5n = 15
if you need to find the number n then
50 - 5n = 15
-5n = -35
n = 7