One set of circle which meets this picture
(x-6)^2 + (y-6)^2 = 36
x^2 + (y-6)^2 = 36
center are P (0,6), N (6,6)
Then, distance between center would be
distance = sqrt ( 6^2 + 0^2 ) = sqrt(36) = 6
Intersection
x^2 + (y-6)^2 = (x-6)^2 + (y-6)^2
x^2 = x^2 -12x +36
-12x + 36 = 0
12x =36
x = (36/12) = 3
(3-6)^2 + (y-6)^2 = 36
9 + (y-6)^2 =36
(y-6)^2 =27
taking the square root of both sides
(y-6) = +/- 3*sqrt(3)
y-6 = +/- 3*sqrt(3)
y = 6 +/- 3*sqrt(3)
The area of the shaded is
the area of two chord topped
circular segments.
this is formula for the area of one of the segments
A=(R^2/2) ( theta - sin(theta) )
R = 6
R^2 = 36
A (of one circular segment) = 18(theta-sin(theta) )
so (1/2)theta = arccos( opp/hyp) =
(1/2)theta = arcos(3/ ( sqrt( ( (3-0)^2 + (6- (6 - 3*sqrt(3))^2)
(1/2)theta = arcos( 3/ sqrt( 9 + (3*sqrt(3)^2 )
(1/2)theta = arcos(3/ sqrt( 9 + 9*3 )
(1/2) theta = arcos( 3/sqrt(36) = arcos(1/2) =pi/3 + 2pi
or -pi/3 + 2pi
but the (1/2)theta is less than pi/2
(1/2)theta = pi/3
theta = 2pi/3
A(one circular segment) = 18( 2pi/3 - sin(2pi/3) )
A(one circular segment) = 18(2pi/3 - sqrt(3)/2 )
so but we have two circular segments
All Area = 36(2pi/3 - sqrt(3)/2) = 44.22130915 square units
Article on determining the area of a circular segment
https://en.wikipedia.org/wiki/Circular_segment#:~:text=In%20geometry%2C%20a%20circular%20segment,a%20secant%20or%20a%20chord.