Question

How many terms are in the arithmetic sequence 7, 0, −7, . . . , −175?

Hint: an = a1 + d(n − 1), where a1 is the first term and d is the common difference.

A. 27
B. 28
C. 29
D. 30

Answer 1

see u got the first term and common difference and the last term..so
\[a_n = -175\]
\[a_1 = 7\]
\[d = -7\]
now use the formula
\[a_n = a_1 + d(n - 1)\]
get n i.e the on of terms :))

Answer 2

so it would be -175=7+(-7) (n-1) ?

Answer 3

yup.:)))good work :))

Answer 4

okay so how do i do it now like can you help me step by step

Answer 5

do i subtract 7 to -175?

Answer 6

first of all subtract -7 on both sides..so u will be having
\[-182 = -7(n - 1)\]
then
do the multiplications required
\[-182 = -7n + 7\]
proceed

Answer 7

so then it would be -189=-7n? and then i divide right?

Answer 8

yeah :))))

Answer 9

but thats 27

Answer 10

good work :)))

Answer 11

thats not done tho right

Answer 12

thts correct

Answer 13

oh jk yeah i got it now thank you so much!

Answer 14

u welcome :))

Answer 15

can you help me with one more problem?

Answer 16

sorry man ...i gtg to class

Answer 17

oh okay thats fine no worries