i need help with this.

Question

In 1994, the number of cassette singles shipped was 81.1 million. In 1997, that number dropped to 42.2 million. Write an equation that gives the number of cassettes shipped, y, in terms of the year, t. Let t=4 represent 1994.

how do yu do this ? thanks (:

Answer 1

y=(-12.97t + 132.97)*10^6

-So for 1999 (t=9) this gives 16.27 million cassettes shipped.

*Sorry if its incorrect (this was my best answer).