How would the flat piece of cardboard look after Tanya opened it?

Answer

To solve this problem, we need to visualize how the cardboard is folded and subsequently how it will appear when opened back up. 1. **Understanding the Fold**: The problem states that Tanya took a rectangular piece of cardboard and folded it in a specific way, ensuring the edges did not overlap. The drawing shows a rectangular piece being folded to form a 3D shape, likely resembling a box or a cube with the sides folded up. 2. **Analyzing the Lines Drawn**: After folding, Tanya marked four lines on the edges of the fold. When the cardboard is opened, these lines will correspond to the edges of the original rectangle. 3. **Opening the Cardboard**: Opening the folded cardboard will unfold it back to its original flat shape but the markings will show where the folds were made. This means that we will see a continuous flat rectangle with four lines indicating the sections of the box/ cube. 4. **Determining the Correct Option**: Among the options provided (A, B, C, D), only the option that represents a single rectangular piece with four lines across it (indicating the folds) will be correct. The option that visually corresponds with the unfolded view of the folded cardboard will be the correct answer. After careful consideration of the visual elements and how folding works, the correct choice is **Option A**. Thus, the cardboard when opened would look like a flat rectangle divided into sections by 4 lines.