Answer:
D. y=x^2-5
Step-by-step explanation:
The triangle ABC is a right angled triangle , right angled at C because it is the angle subtended by the diameter
Now OA = OB = OC = 4 cm (radii)
AB = OA + OB = 8 cm
By pythagoras theorem ,


AC =4 
shade region area = area of semicircle - area of triangle
=
- 1/2 × base × height
=1/2 × 16
- 1/2 × 4 × 
=8
- 8
=8(
)
C = 48
c = 2a - 4
48 = 2a - 4
48 + 4 = 2a
52 = 2a
52/2 = a
26 = a <==