The sum of the first 10 terms of an arithmetic sequence is 530. What is the first term if the last term is 80 and the common difference is 2.

no one knows lol

step-by-step explanation:

.19875994384

step-by-step explanation:

1699/ 8548

step-by-step explanation:

given that ab is divided into equal parts as

ac, cd, de, ef, fg, gh, hi, ib.

from this we find that f is the midpoint of ab.

so using mid point formula we find

f = (3,7)

similarly considering fb, we get

h = mid point of fb = ((6,6) and g, mid point of fh is

g = (9/2, 13/2)

i is mid point of hb

so i =(15/2,11/2)