Answer: Choice A
S9 = (9/2)*(2+26)
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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: 3 4/5
Explanation: 19 divided by 5 is 3 4/5
2x + 12 = 18
18 - 12 = 6
2x = 6
x = 3
Answer:
SRO and QRO
Step-by-step explanation:
Hope this helps!
Answer:
3/12
Step-by-step explanation:
10-7 is 3, so its 3/12.