2(3) - 3 + 7 = 6 - 3 + 7 = 10
Answer:
n = 9
Step-by-step explanation:
20 + 18 + ... + 6 + 4
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a = 20 ; d = -2 ; n = ?
--------
4 = 20 + (n-1)(-2)
-16 = (n-1)(-2)
---------
n-1 = 8
n = 9
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S(9) = (9/2)(20+4)
S(9) = 4.5*24
S(9) = 108
Answer: the answer is B
Step-by-step explanation:
Answer:
10.8 units
Step-by-step explanation: