Mathematics Question and Solution
a = (6-b) cm.
b is the radius of the two congruent inscribed yellow half circles.
6 cm is the radius of the ascribed half circle and also, the diameter of the inscribed circle.
c = ½(6)
c = 3 cm.
c is the radius of the inscribed yellow circle.
d = (3+b) cm.
It implies, calculating b.
(6-b)²+3² = (3+b)²
36-12b+b²+9 = 9+6b+b²
36 = 18b
b = 2 cm.
Again, b is the radius of the inscribed two equal half circles.
Therefore, area blue is;
Area half circle with radius 6 cm - Area circle with radius 3 cm - 2(area half circle with radius 2 cm).
= ½(6²)π-π(3²)-2(½*π(2²))
= 18π-9π-4π
= 5π cm²
