Determine arithmetic mean of the numbers f(x1), f(x2) for f(x) = x/2-6 ; x1 = -8, x2 = 10

We'll determine the arithmatic mean of the numbers f(x1)
and f(x2):

A.M. = [f(x1) +
f(x2)]/2

To compute the value of A.M., we'll have to
compute the values of f(x1) and f(x2).

For this reason,
we'll substitute x1 and x2 in the expression of f(x).

For
x1 = -8, we'll get:

f(-8) = -8/2 -
6

f(-8) = -4 - 6

f(-8) =
-10

For x2 = 10, we'll
get:

f(10) = 10/2 - 6

f(10) =
5 - 6

f(10) = -1

Now, we'l
substitute f(x1) and f(x2) by the values of f(-8) and f(10) in the expression of
A.M.

A.M. = [f(-8) +
f(10)]/2

A.M. =
(-10-1)/2

A.M. =
-11/2