Answer:
Length ≈ 20 feet (rounded down nearest 10th feet)
Width ≈ 20 feet (rounded up to nearest 10th feet)
Explanation:
Find Length and Width
Width = Length - 4 feet
Area = 42 ft²
Area = L x W
42 = L x (L - 4)
42 = 2L - 4
42 + 4 = 2L - 4 + 4
2L = 46
2L/2 = 46/2
L = 23
L ≈ 20 feet
Width = 23 - 4
Width = 19 feet
Width ≈ 20 feet