The standard equation for a circle with center at (h,k) and radius r is
(x-h)^2 + (y-k)^2 = r^2, where (h,k) is the center of the circle.
The formula for the circumference of a circle is C = 2pi*r. In this particular problem, we need to determine the radius of the circle. That radius is: r = C/[2pi]. Here, C = 22pi, so we get r = 22pi/[2pi], and so r^2 = 11^2.
Putting to use the given info, we have:
(x+14)^2 + (y-5)^2 = 11^2
Answer:
Step-by-step explanation:
Given
See attachment for farm
Required
The cost of fencing the farm
First, calculate the radius of the farm.
The radius is represented with AC.
So, we have:
---- distance formula
So, we have:
Hence:
--- radius
Calculate the circumference of the circle
If 1 yard costs $30, 31.4 yards will cost:
Recall the sum identity for cosine:
cos(a + b) = cos(a) cos(b) - sin(a) sin(b)
so that
cos(a + b) = 12/13 cos(a) - 8/17 sin(b)
Since both a and b terminate in the first quadrant, we know that both cos(a) and sin(b) are positive. Then using the Pythagorean identity,
cos²(a) + sin²(a) = 1 ⇒ cos(a) = √(1 - sin²(a)) = 15/17
cos²(b) + sin²(b) = 1 ⇒ sin(b) = √(1 - cos²(b)) = 5/13
Then
cos(a + b) = 12/13 • 15/17 - 8/17 • 5/13 = 140/221
I am assuming this is a triangle.....P = a + b + c
P = 2a - 3 + 2a + 3a + 1....combine like terms
P = 7a - 2 <==