Answer:
Step-by-step explanation:
Let w represent the width of the rectangle. Then the length is 5/4w, and the area is ...
A = LW
320 in² = (5/4w)(w)
256 in² = w² . . . . . . . . . multiply by 4/5
16 in = w . . . . . . . . . . . . take the square root
5/4w = 5/4(16 in) = 20 in . . . . the length
The length of the rectangle is 20 inches; its width is 16 inches.