The length is 42 inches and the width is 14 inches.
Work Step by Step
The formula for the perimeter of the rectangle is width + width + length + length. Since the length is stated in terms of the width, we can let w represent the width. Since the length is three times the width, and the width is w, the length is 3w The perimeter of the rectangle is 112, so we set up the following equation: w + w + 3w + 3w = 112 8w = 112 Divide both sides by 8. w = 14 Since w = 14, the length is 3 $\times$ width = 3 $\times$ 14 = 42.