Please help Determine if the given sequence is geometric. If the sequence is geometric, find the common ratio. −4, −1, 1, −4,...

A. The sequence is geometric. The common ratio is. (Type an integer or a simplified fraction.)

B. The sequence is not geometric.

C. It cannot be determined whether the sequence is geometric or not

B

Step-by-step explanation:

To determine if a sequence is geometric, the terms need to have a common ratio. This means that to get from one term to the next, you need to multiply by the same number. Here's an example geometric sequence:

1) 2, 4, 8, 16, 32...

2) 4, 6, 9...

As you can see, to get from one term to the next in both of these sequences, you need to multiply by a certain number [the common ratio]. In sequence one, this number is 2. You need to multiply a term by 2 to get to the next term. In the second sequence, this number is 3/2. To find this certain number/common ratio, you can set the terms into ratios:

9/6=3/2

6/4=3/2

This ratio between the terms we get is the common ratio. Multiplying by this number will get you to the next term.

In this case [-4, -1, 1, -4...]:

The ratios produced by the terms clearly aren't the same here, so the sequence is not geometric.

step-by-step explanation: so we look at the formula un = a + (n-1)d

un is the amount of seats

n is the nth term aka row number

a is the original sequence/row number

d is the difference between each term

so in this a=22 d=6 and n can remain as n because we are simply formjng a rule

lets put these in the equation

un=22+(n-1)(6)

this is your answer to part a

however

lets double check that this is correct, we'll try putting it into the second term

un=a+(n-1)d

u2=22+(2-1)(6)

u2=22+6

u2=28

as the question said the second row has 28 seats so now we know the formula we made is correct.

as for part b

un=a+(n-1)

its asking us to find a row with 100 seats.

remember un was the amount of seata so all we do is substitute this in.

un=100 a=22 d=6

un=a+(n-1)d

100=22+(n-1)(6)

so now we simplify to find n which is the row number.

100-22=22+(n-1)(6)-22

78=(n-1)(6)

78/6=(n-1)(6)/6

13=n-1

13+1=n-1+1

14=n

so now we know that in the 14th row there is 100 seats.

hope this and that you understood! its my first time using the app or anyone out on here : p its also me to revise so a bunch! ask more questions if you dont understand ☺

y=-2.5x+12.5

step-by-step explanation:

5y=2x+10

y=0.4x+2

slope=-2.5

5=-2.5*3+b

b=12.5