The area of a rectangular field is equal to 800 square meters. Its perimeter is equal to 120 meters. Find the width of this rectangle.  Choose the correct option:	A) 5	B) 10	C) 15	D) 20	E) 25

Rationale: "l * w = 800 : area , l is the length and w is the width . 2 l + 2 w = 120 : perimeter l = 60 - w : solve for l ( 60 - w ) * w = 800 : substitute in the area equation w = 20 and l = 40 correct answer d"
Answer: D