Question

What is the sum of a 17–term arithmetic sequence where the first term is 6 and the last term is –90? please help?

Answer 1

Is there a formula for this?

Answer 2

didn't i already help you with this one??

Answer 3

ya but it was wrong :/

Answer 4

-714

Answer 5

Okay! thank you so much. yeah that's a different answer than the one from last time. thank you

Answer 6

i gave you the formula

Sn = n(A1+An)/2

Answer 7

= 17(6-90)/2

= 17(-84)/2

= -714

Answer 8

Oh sorry. lol I thought you meant 17 was the answer but now i get it. Thank you for giving me the equation too!