Question

will medal and fan for help (so help please)
find the 50th term of the sequence 5, -2, -9, -16, ...

A. -352
B. -343
C. -338
D. -331

Answer 1

here common diff d=-2-5=-7 and a=5
n th term=a+(n-1)d

Answer 2

where n is number of term a is first term and d is common difference

Answer 3

so it would be a(50)=5+(50-1)*-7

Answer 4

right

Answer 5

yes

Answer 6

which would turn into a(50)=55-1*-7
which would than be a(50)=54*-7
which would produce a(50)=-378

Answer 7

correct

Answer 8

5+(50-1)*-7
=5-7*49

Answer 9

and then it would be5-343
which would then be -348

Answer 10

right

Answer 11

5-343=-338

Answer 12

so it would be C. correct

Answer 13

yes

Answer 14

what about another question

Answer 15

which one

Answer 16

find the arithmetic mean of an of a\[a _{n-1}=3.9\] and \[a _{n+1}=7.1\]

Answer 17

put 3.9=a+(n-1-1)d
and 7.1=a+(n+a-1)d and solve then get a and d

Answer 18

so it would be 1.7

Answer 19

i mean 1.6

Answer 20

3.9=a+(n-1-1)d
7.1=a+(n+1-1)d
subtract it
7.1-3.9=a+nd-a-nd+2d
3.2=2d
d=1.6

Answer 21

so i was right

Answer 22

now solve a

Answer 23

3.6

Answer 24

u try to find AM so u can simple add and divide by total numbers of terms

Answer 25

so i am right