Question

HELP?!?! I dont understand how to do this, can someone explain???
Find the common ratio of the sequence.
–4, 8, –16, 32, . . .

Answer 1

Geometric Sequences

In a Geometric Sequence each term is found by multiplying the previous term by a constant.

Example:

2, 4, 8, 16, 32, 64, 128, 256, ...
This sequence has a factor of 2 between each number.

Each term (except the first term) is found by multiplying the previous term by 2.

http://www.mathsisfun.com/algebra/sequences-sums-geometric.html

Answer 2

Er, I think Adrianna has missed the sign thing. Each term is -2x the previous one, isn't it? So the common ratio is 1:-2. (Or you could express this in a number of other ways by multiplying both sides by any common multiplier.)

Answer 3

Its different, i tried that already @Adrianna.Gongora

Answer 4

Is it -2? @Biffo

Answer 5

I was showing him an example to show him... That is why I put a site he said he
"HELP?!?! I dont understand how to do this, can someone explain???"

Answer 6

Another example is

5 -5 5 -5 5 -5 ......

The common ratio is (-1) and the start number is 5.
Every term you can find by multiplying the previous by -1.

Answer 7

this is the pattern I noticed
from -4 -> 8 you add 12
from 8 -> -16 you subtract 24
from -16 -> 32 you add 48
it's like going by 12's but it goes back and forth between adding and subtracting .
@andrea_thecat @brunotbb @Biffo

Answer 8

Oh, so it would be -2? Correct??? @Adrianna.Gongora

Answer 9

im not sure hold on ...

Answer 10

what are your answer choices?

Answer 11

Oh yes! multiply by -2 and you get the next term!

Answer 12

^^ then yes it is c:

Answer 13

I think I answered this a while ago. The ratio of one term to the next is 1:-2 or, you could put it \[-\frac{ 1 }{ 2 }\].

However, the answer required, I think, is the other way round. The common ratio of one term to the previous one is the inverse of the minus a half thing. So the correct answer would be -2.