PLEASE HELP ASAP!!
The 7th term of a geometric sequence is 31.45728. The common ratio is –0.8. Find the first term of the sequence.

The first term of the sequence is -120.

Step-by-step explanation:

The formula for the "nth" term of a geometric sequence is shown below:

an = a0*r^(n-1)

Where an is the nth term, r is the ratio and n is the position of the term on the sequence. For this problem we want to find what is the initial term, a0, so we will isolate it in the formula as shown below:

a0*r^(n-1) = an

a0 = an/[r^(n-1)]

We then apply the data given to us

a0 = 31.45728/[-0.8^(7-1)]

a0 = 31.45728/[-0.8^6] =31.45728 /-0.262144= -120

The first term of the sequence is -120.

207/8 is the right

i think the answer is b.

step-by-step explanation:

not 100% sure though.