Question

Need the answer to​ this thank you!

Answer 1

Answer:

n = 4

Step-by-step explanation:

Use the explicit formula of a arthmetic sequence: an = a1 + d(n - 1)

a1 = -70

d = -10

an = -100

Do all of the steps and plug all the numbers with the formula.

So -100 = -70 - 10(n - 1)

-100 = -70 - 10n + 10

-100 = -60 - 10n

-100 + 60 = -40

-40 = -10n

-40/-10n = -10n/10

n = 4

So the final answer is n = 4. Just follow all of the steps and you will understand how I got my answer. Hope it helped!