If a function, f(x) is translated d units downwards, the new function would be
f(x) - d
The original function that we were given is
y = 3^x
It can also be written as
f(x) = 3^x
the function after the shift is
y = 3^x - 2
It can also be written as
f(x)' = 3^x - 2
By comparing with the function stated earlier, - d = - 2
Thus, the function was translated 2 units downwards
D) Down
