Sum = n/2[2a + (n - 1)d] where a = first term, n = number of terms and d = common difference
(a) 30/2(2 x 5 + (30 - 1) x d) = 1455
10 + 29d = 1455 / 15
29d = 97 - 10
d = 87 / 29 = 3
(b) 7/2(2 x 9 + (7 - 1)d) = 0
18 + 6d = 0
6d = -18
d = -3
Answer:
on what? I will, but on what?
Answer:
It has been a while. I think it is ASA and AAS
1/5^2 = 1/25
1/5^1 = 1/5
1/5^0 = 1
1/5^-1 = 5
1/5^-2 = 25