Ask
your own question, for FREE!
Mathematics
8 Online
OpenStudy (anonymous):
What is the sum of a 22–term arithmetic sequence where the first term is 56 and the last term is –28?
Still Need Help?
Join the QuestionCove community and study together with friends!
OpenStudy (anonymous):
\[ a_1 =56\\ a_2 = 56 -r\\ a_3= 56 -2r\\ a_{22} = 56- 21\ r=-28\\ 21 r = 56 + 28=84\\ r= 4 \]
OpenStudy (anonymous):
\[ sum = 56 -r + 56-2r +\cdots + 56 - 21 r\\ 21(56) -4(1+2 +\cdots +21)=1176-4 (21)(22)/2=252 \]
Can't find your answer?
Make a FREE account and ask your own questions, OR help others and earn volunteer hours!
Join our real-time social learning platform and learn together with your friends!
Join our real-time social learning platform and learn together with your friends!
Latest Questions
thereneelg:
Okay....I'm doing a group solo for choir. Auditions are Tuesday (?), Any tips on
Arizona:
my Rolling stone airpods won't connect and I got them about a year ago is there t
Arizona:
can someone check out my essay i'm doing in my senior English class about the McD
IcedShots:
I was wondering, is there anybody on here around my age? Im turning 15 on December 1 ud83dude0a.
thatonenerd:
Use Hvap of water = 40.7 kJ/mol, c of water = 4.184 J/g.u00b0C, and molar mass of HO = 18.
letrasbonitasz:
Typography plays an important role in digital communication. Different font styles can make social media profiles, usernames, messages, and creative designs
Bounty:
tested love: im so over love it acquires patience i don't have trials an tribulations yet my souls the only one taken i give 90 you give 10 you say that you
SaltySuga:
is it possible to tell how deep a cut is by an open wound? like would i be able t
AndreW2002:
I'm trying to change my profile picture but it keeps saying "Either a error occurred, or you tried to upload a gif" but it's not a gif that I'm using, it's
thereneelg:
Okay....I'm doing a group solo for choir. Auditions are Tuesday (?), Any tips on
14 hours ago
0 Replies
0 Medals
Arizona:
my Rolling stone airpods won't connect and I got them about a year ago is there t
20 hours ago
3 Replies
0 Medals
Arizona:
can someone check out my essay i'm doing in my senior English class about the McD
1 day ago
1 Reply
0 Medals
IcedShots:
I was wondering, is there anybody on here around my age? Im turning 15 on December 1 ud83dude0a.
21 hours ago
3 Replies
0 Medals
thatonenerd:
Use Hvap of water = 40.7 kJ/mol, c of water = 4.184 J/g.u00b0C, and molar mass of HO = 18.
2 days ago
5 Replies
0 Medals
letrasbonitasz:
Typography plays an important role in digital communication. Different font styles can make social media profiles, usernames, messages, and creative designs
4 days ago
3 Replies
1 Medal
Bounty:
tested love: im so over love it acquires patience i don't have trials an tribulations yet my souls the only one taken i give 90 you give 10 you say that you
2 days ago
7 Replies
2 Medals
SaltySuga:
is it possible to tell how deep a cut is by an open wound? like would i be able t
5 days ago
5 Replies
1 Medal
AndreW2002:
I'm trying to change my profile picture but it keeps saying "Either a error occurred, or you tried to upload a gif" but it's not a gif that I'm using, it's
6 days ago
3 Replies
0 Medals