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:
option A. 21 sec
Step-by-step explanation:
Speed = the distance over the time
Given:
Speed = 2 m/s and distance = 42 m and time = t
So,
2 = 42/t
Solve for t
t = 42/2 = 21 sec.
The answer is option A. 21 sec
There are 4 sets of 15 minutes in a hour so you would take the 10 airplanes and multiply it by 4 and get 40 as your answer
In 1 hour 40 planes with arrive at the airport
Answer: Im pretty sure it is the equal sign with the line between it
pretty sure that is it tho
Hope that helped
Step-by-step explanation:
