SOLUTION: the number of terms in the following arithmetic sequence... 3a-5, a+1, 7-a,..., 109-35a
Algebra
->
Sequences-and-series
-> SOLUTION: the number of terms in the following arithmetic sequence... 3a-5, a+1, 7-a,..., 109-35a
Log On
Algebra: Sequences of numbers, series and how to sum them
Section
Solvers
Solvers
Lessons
Lessons
Answers archive
Answers
Click here to see ALL problems on Sequences-and-series
Question 1033214
:
the number of terms in the following arithmetic sequence...
3a-5, a+1, 7-a,..., 109-35a
Answer by
mananth(16946)
(
Show Source
):
You can
put this solution on YOUR website!
3a-5, a+1, 7-a,..., 109-35a
first term = 3a-5
d= (a+1)-(3a-5) = -2a+6
tn = 109-35a
109-35a = (3a-5)+(n-1)(-2a+6)
n=20