If the perimeter is 16, the side length is 4 units.
To find the area of the shaded sections, you will use the fractional part that each section represents and multiply that fraction by the total area of the square.
Area of DEA is 1/4 of 16 square Units (4 x 4).
1/4 x 16 = 4 square units
Area of EFB is 1/8 of 16 square units.
1/8 x 16 = 2 square units
4 square units +2 square units equals 6 square units.
The area of the shaded region is 6 square units.