How do you construct a rectangle? Plz show all steps, it's for FLVS. I really need help

Step-by-step explanation:

1. Choose arbitrary points A and B in the plane and draw segment AB.

2. Raise a perpendicular m to AB at A.

3. Raise a perpendicular n to AB at B.

4. Choose an arbitrary point C on line n.

5. Drop a perpendicular from point C to line m. Let D be the foot of this perpendicular.

6. Then quadrilateral ABCD is a rectangle.

area of part 1:

a1=base*height/2=(8+2)*(8-2-2-1)/2=10*3/2=15 ft^2

area of part 2:

a2=length*width=(8+2)*1=10 ft2

area of part 3:

a3=length*width=8*2=16 ft2

total shaded area : a1+a2+a3=41 ft2

total area of the reactangle : a=16*8=128 ft2

total area of the nonshaded region : 128-41=87 ft2