Answer:
9 inches
Explanation:
Area of the rectangular cardboard = Length * Width ... 1
Given the area of the cardboard = 36-square inches
If the length of the cardboard can be found by dividing its area by its width, then Length = Area/Width ... 2
Given the width to be 4 inches
Length = 36 in²/4 in
Length of the cardboard = 9 inches