Respuesta :

we have that
y = 2(0.45)^x

in this problem 
2-----------> is the Coefficient
0.45-------> is the Base
x-----------> is the Exponent

we know that
If the base  is less than 1 (but always greater than 0), the function will be exponential decay
It is decay because as x values increase, y values decrease.
0.45 < 1  and 0.45 > 0
therefore

the equation
y = 2(0.45)^x
represents exponential decay

the answer is
exponential decay