Respuesta :

The exponential function that represent the value of Mary's Computer is:

[tex]f(t)=520(0.25)^{t} [/tex]

for t=0, we get:

[tex]f(0)=520(0.25)^{0} \\ \\ f(0)=520(1) \\ \\ f(0)=520[/tex]

Interpretation:
The exponential function shows the value of her computer after t years, so by replacing t=0, we will get the value of computer the year she bought it.

Thus, the value of computer when Mary bought it was $520.