Asked by Britney OW
An Arithmetic sequence has a tenth term of 17 and a fourteenth term of 30, ind the general term
PLEASE HELP!!!!
PLEASE HELP!!!!
Answers
Answered by
Reiny
a+9d = 17
a+13d = 30
subtract them
4d = 13
d=13/4 = 3.25
then a + 9(3.25) = 17
a = -12.25
term(n) = a + (n-1)d
= -12.25 + (n-1)(3.25)
= -12.25 + 3.25n - 3.25
term(n) = 3.25n - 15.5
check:
term(10) = 32.5 - 15.5 = 17
term(14) = 14(3.25)-15.5 = 30 , all is good
a+13d = 30
subtract them
4d = 13
d=13/4 = 3.25
then a + 9(3.25) = 17
a = -12.25
term(n) = a + (n-1)d
= -12.25 + (n-1)(3.25)
= -12.25 + 3.25n - 3.25
term(n) = 3.25n - 15.5
check:
term(10) = 32.5 - 15.5 = 17
term(14) = 14(3.25)-15.5 = 30 , all is good
Answered by
Britney OW
thank you :)