The formula for a circle is (x - h)^2 + (y - k)^2 = r^2
Where (h, k) is the center and r is the radius.
x^2 + (y - 8)^2 = 25
25 = r^2
So the radius is sqrt 25 or 5.
Radius = 5
Given:
The demand function is,

The total revenue function is,

Answer:
7. -8/3
8. 4/35
9. -21/50
10. 35/64
11.-25/54
Answer:
AC = 6
Step-by-step explanation:
y is the dimension of the horizontal segment (see the attached image).
The hypotenuses are the same dimension, so:
(x+4)^2=(x/2)^2+y^2
(3x-8)^2=(x/2)^2+y^2
So,
(x+4)^2 = (3x-8)^2
x+4 = 3x-8
x-3x = -8-4
-2x = -12
x = 6
And x is the dimension of the segment AC.