Answer:
6 cm
Step-by-step explanation:
We start by defining the length and the width. Lets call the length L and the width W.
We know that the length L is 17 more than 3 times the width W, which to put into an equation: L = 17cm + 3*W
We know what the perimeter is (82cm) and we also know the equation for the perimeter of a rectangle which is 2L + 2W = P = 82. Substitute the value we have for L and we get 2(17+3W) + 2W = 82.
Simplify to get 8W = 48 so we get W = 6cm.
