Answer:
The diameter that will reward with the largest pizza is 14 in
Step-by-step explanation:
The perimeter of a sector of a circle is:
P = 2r + l
l = rθ
P = 2r + rθ
P=28 inches
28=2r + rθ
28-2r=rθ
θ=(28-2r/r)
=(2*14 - 2*r)/r
=2(14-r)/r
Area of the sector of the circle is:
A = r²/2 * θ
A = r²/2 * 2(14 - r)/r
A = r² * (14 - r)/r
A = r(14 - r)
A = 14r - r²
For the maximum area:
A = 14r - r²
A' = 14 - 2r
Set A' = 0
14 - 2r = 0
14= 2r
r = 7 in
The diameter (D) of the circle is twice of the radius:
D = 2r = 2 * 7= 14 in
The maximum area is:
A = 14r - r²
r = 7 in
A = 14 * 7 - 7²
A = 98 - 49
A = 49 in²