Dahiaaan,
En los dos casos, el area sombreada será igual:
As = At - Ans
As = area sombreada
At - area total
Ans = area no sombreada
Asi:
1) At = y^2
Ans= 2x^2
As = y^2 - 2x^2
2) At = x^2
a) As = x^2 - 3/4x^2
= 1/4x^2
b) As = x^2 - 7/8x2
= 1/8x^2
c) As = x^2 - 8/9x^2
= 1/9x^2
d) As = x^2 - 5/9x^2
= 4/x^2