Question

ind an equation for the nth term of the arithmetic sequence.

a14 = -33, a15 = 9

Answer 1

what's the formula for an arithmetic sequence ?

Answer 2

not sure

Answer 3

general form equation for an arithmetic sequence ? you don't know ?

Answer 4

No

Answer 5

\[\large\rm a_n=a_1 +(n-1)d\]you need this equation for an arithmetic sequence
where n= term that we need nth
a_1 = first term
d=common difference
in order to write the equation we have to find first term and common difference

Answer 6

formula to find common difference \[\rm d= a_2- a_1\]subtract the term by one previous term

Answer 7

then you get 42 ohh i get it now

Answer 8

an = -579 + 42(n - 1)
so this is the answer right

Answer 9

substitute a_!4 and a_15 term into the equation
when n=14 a_14 =-33
same with 15th term and then solve for d

Answer 10

how did you ge t -579 for first term ?

Answer 11

wait what?

Answer 12

write two equations substitute
n=14 a_14 =-33

Answer 13

Thats what i did

Answer 14

\[\large\rm a_n=a_1+(n-1)d\]
a_14 means n=14 remember n represent the number of the term
so \[\rm a_{14}=a_1+(14-1)d\]
and a_14 =-33 so plug that in
\[\rm -33=a_1+(14-1)d\]

Answer 15

then that's what i asked how did you get -579 for first term......

Answer 16

Oh i thought you were sayiing i was wrong thats why i said wait what

Answer 17

i don't know i'm saying show ur work
how did you get -579