​ Does each equation represent exponential decay or exponential growth?

If the number that is being raised to the power of  t is in the interval  (0, 1) , it is exponential decay.

 

If the number that is being raised to the power of  t  is greater than  1 , it is exponential growth.

 

For example,

 

y  =  3.7(0.2)^t       Here,  0.2  is being raised to the power of  t .

 

0.2  is in the interval  (0, 1)  so this equation represents exponential decay.

 

See if you can figure out the others.

 

And for this one...

 

g(x)  =  2.1(x)

 

Here, there is no exponent. So this equation is neither exponential growth nor exponential decay.