Isabelle is using a square piece of cardboard to make a box without a lid. She cuts 2-inch squares from each corner and folds up the edges. The finished box has a volume of 98 cubic inches. Which equation can be used to find the dimensions of the original cardboard piece?
2(w – 4)² = 98
2w² – 8w = 98
w² – 4 = 98
w² – (w – 4)² = 98