Answer:
y= 7^-t
Step-by-step explanation:
Equation for exponential decay:
An equation represents exponential decay if a term between 0 and 1 is elevated to the independent variable.
In this question:
First option 4 is elevated, so not exponential decay.
Second option:
[tex]7^{-t} = \frac{1}{7^t} = (\frac{1}{7})^{t}[/tex]
[tex]0 < \frac{1}{7} < 1[/tex], thus, the second option represents exponential decay.
