Question

Write an expression to describe a rule for the sequence. Then find the 100th term.

-4, 1, 6, 11, 16, . . .

Answer 1

it always adds 5

Answer 2

oh yeah.. then the 100th term is 16 times 95 which is 1520

Answer 3

i think...

Answer 4

I am not familiar with sequences. how did you get 16, and 95?

Answer 5

i have no idea... now that i think of it i really dont know -_-

Answer 6

because there are 5 so far, and we want #100, so it is 95 left right?
and the last one is 16 :)

Answer 7

is -4 for n=1 ?

Answer 8

do we start the sequence with "1"?

Answer 9

first term - term n=1 - is -4, right ?

Answer 10

yes

Answer 11

ok, then this formula will work:
multiply n by 5 and subtract 9

if n=1, we have n*5=5-9=-4
if n=2, we have 2*5=10-9=1
if n=3, we have 3*5=15-9=6

Answer 12

\[n_{th} term=5 \times n -9\]

Answer 13

you lost me there dude.. i gonna be honest with u, i have no idea what your saying :)

Answer 14

I tried some formulas and came up with the one above :)
in the post, I just shared with you how I checked it

look at the equation above, try it for some term of the sequence

Answer 15

\[a_n=a_0+d(n-1)\\
d=5\\
a_0=-4\\
a_n=-4+5(n-1)=5n-9\]

Answer 16

\[a_{100}=5\cdot100-9=491\]