If a length of a rectangle is four times its width. what is its perimeter is 90m. how can I find the dimentions

W = width

4w = length

perimeter = 2 (length) + 2 (width)

perimeter = 2 (4w) + 2w

perimeter = 8w + 2w

perimeter = 10w

90 = 10w

9 = w

length = 4w, 4 (9) = 36.

Length is 36 m. Width is 9 m.