Answer: Choice A
S9 = (9/2)*(2+26)
===============================================
The formula is
Sn = (n/2)*(a1+an)
where
Sn = sum of the first n terms (nth partial sum)
n = number of terms
a1 = first term
an = nth term
In this case,
n = 9
a1 = 2 (plug in n = 1 into the formula an = 3n-1 and simplify)
an = a9 = 26 (plug n = 9 into the formula an = 3n-1 and simplify)
So,
Sn = (n/2)*(a1+an)
S9 = (9/2)*(2+26)
will help us find the sum of the first 9 terms of this arithmetic sequence
Answer:
23 maybe because there is a 90 degree angle
Answer:
I'm not sure, but I'll try
Step-by-step explanation:
(Side)^2 = (Hypotenuse)^2 - (Side)^2
(Side)^2 = (9)^2 - ( √ 65 )^2
(Side)^2 = (81) - (65)
(Side)^2 = 16
Take root of answer
Side = √16
Side = 4
Answer = 4
Answer:
The unknown number is 2/15.
Step-by-step explanation:
4/5+x=14/15
x=14/15-4/5
x=14/15-12/15
x=2/15
