If the sum of first 9 terms of an A.P is equal to sum of its first 11 terms, then what is the sum of its 20 terms?
2 answers:
Answer:
Put the values into the formula....let me know if you need help....
Step-by-step explanation:
Answer: 0
Step-by-step explanation:
Sum of the first 9 terms = 9/2 (2a + 8d)
Sum of the first 11 terms = 11/2 (2a + 10d)
S9 = S11
9a + 36d = 11a + 55d
2a = -19d
2a + 19d = 0...........(1)
S20 = 20/2 (2a + 19d)
= 20/2 (0) . .. ............from (1)
S20 = 0
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Answer:
C 10 columns and 12 rows
Step-by-step explanation:
c = columns
r = rows
5c + 5c = 10c
6r + 6r = 12r
10 columns and 12 rows
The answer is C
X = games won
y = games lost
x + y = 72
x = 2y + 15
2y + 15 + y = 72
3y + 15 = 72
3y = 72 - 15
3y = 57
y = 57/3
y = 19 <=== lost games
x = 2y + 15
x = 2(19) + 15
x = 53 <=== won games
On which one do you need help with?
Answer:
less than or equal to
Step-by-step explanation:
4 dollars. 26-6=20. 20/5=4
