Find the sum S = 1 + 3 + 5 + · · · + 13 + 15 = X 7
n=1
(2n + 1) by doing the following:
Copy down the series S in increasing order.
Underneath this, write the series S in decreasing order.
Add the two lines by adding the pairs of numbers in each column.
Simplify the result. [Hint: Determine how many terms are being added together
on the right hand side.]
Solve for S.

17 1/3

step-by-step explanation:

ummm seems that u didnt post the attachement !

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)