Which sequences are geometric? Check all that apply.

–2, –4, –6, –8, –10, …
16, –8, 4, –2, 1
–15, –18, –21.6, –25.92, –31.104, …
4, 10.5, 17, 23.5, 30, …
625, 125, 25, 5, 1, …

The geometric sequences are:

16 , -8 , 4 , -2 , 1 ⇒ 2nd

-15 , -18 , -21.6 , -25.92 , -31.104, ⇒ 3rd

625 , 125 , 25 , 5 , 1 , ⇒ 5th

Step-by-step explanation:

In the geometric sequence there is a constant ratio between each two consecutive terms

Let us find which sequence has  a constant ratio between its consecutive terms

-2 , -4 , -6 , -8 , -10

∵ -4 ÷ -2 = 2

∵ -6 ÷ -4 = 1.5

- No constant ratio between the consecutive terms

∴ The sequence is not geometric

16 , -8 , 4 , -2 , 1

∵ -8 ÷ 16 = -0.5

∵ 4 ÷ -8 = -0.5

∵ -2 ÷ 4 = -0.5

∵ 1 ÷ -2 = -0.5

- There is a constant ratio -0.5 between the consecutive terms

∴ The sequence is geometric

-15 , -18 , -21.6 , -25.92 , -31.104,

∵ -18 ÷ -15 = 1.2

∵ -21.6 ÷ -18 = 1.2

∵ -25.92 ÷ -21.6 = 1.2

∵ 31.104 ÷ 25.92 = 1.2

- There is a constant ratio 1.2 between the consecutive terms

∴ The sequence is geometric

4 , 10.5 , 17 , 23.5 , 30,

∵ 10.5 ÷ 4 = 2.625

∵ 17 ÷ 10.5 = 1.619047619

- No constant ratio between the consecutive terms

∴ The sequence is not geometric

625 , 125 , 25 , 5 , 1 ,

∵ 125 ÷ 625 = 0.2

∵ 25 ÷ 125 = 0.2

∵ 5 ÷ 25 = 0.2

∵ 1 ÷ 5 = 0.2

- There is a constant ratio 0.2 between the consecutive terms

∴ The sequence is geometric

720

step-by-step explanation:

first i did work 2nd i did work and 3rd i did work

do you have a picture of the table