Question

Find S(n) for the given arithmetic series.
a = 18 d = -10 n = 12
a.) -552
b.) -888
c.) 768
d.) -444

Answer 1

do u knw the formula for S(n) ?

Answer 2

\[S(n)=\frac{n}{2} (2a+(n-1)d)\]

Answer 3

use that ! :)

Answer 4

wow that looks insanely hard lolz thanks a bunch!