Shadow area = large triangle area (base is 8+6, height is 8)- white area in the lower left corner.

The area of the white part in the lower left corner = the area of a big square-1/4 the area of a circle with a radius of 8.

(1) White area in the lower left corner:

8×8- 1/4×3. 14×8?

=64-50.24

= 13.76(cm？ )

(2) Shadow area:

(8+6)×8÷2- 13.76

=56- 13.76

=42.24(cm？ )