Find the 7th term in the
sequence
-1, -3, -9,...

-729

Step-by-step explanation:

First, note that the sequence is increasing not linearly. Thus, this is a geometric sequence.

The explicit formula for a geometric sequence is:

Where a is the first term, r is the common ratio, and n denote the nth term.

So, from the sequence, we can see that the first term a is -1.

Also, each subsequent term is 3 times that of the previous one. In other words, the common ratio r is 3.

Thus, substituting:

So, to find the 7th term, substitute n for 7:

Simplify:

And that's our answer :)