请帮我解这道题---**Extraction Content:** **Problem Type/Topic:** * 题型 1: 正方体的相对面问题 (Problem Type 1: Opposite faces of a cube problem) **Question Stem:** * 典例9: 如图 1.2-14 是一个正方体的表面展开图，如果正方体的任意两个相对面上标注的值相等，那么x+y=______。 * **Translation:** Example 9: As shown in Figure 1.2-14, this is a net of a cube. If the values marked on any two opposite faces of the cube are equal, then x+y=______. **Chart/Diagram Description:** * **Type:** Net of a cube (正方体的表面展开图). * **Figure Label:** 图 1.2-14 (Figure 1.2-14) * **Main Elements:** The diagram shows a 2D net composed of 6 square faces, arranged in a specific pattern. The faces are labeled with numbers or algebraic expressions. * The net can be visualized as a central column of three squares, with one square attached to the left of the middle square, and two squares attached to the right of the bottom-most square. * The values on the squares are: * Top square (above the middle column): 9 * Left square (to the left of the middle square in the central column): 2x * Middle square (in the central column): y * Right square (to the right of the middle square in the central column): 8 * Bottom-left square (below the middle square in the central column): 9 * Bottom-right square (to the right of the bottom-left square): 10 **Implied Mathematical Relationships (from the problem description and net structure):** Based on the properties of a cube net, specific pairs of faces are opposite to each other when folded. Given the condition that "values marked on any two opposite faces of the cube are equal": 1. The face labeled '2x' is opposite to the face labeled '8'. * Therefore, 2x = 8. 2. The face labeled 'y' is opposite to the face labeled '10'. * Therefore, y = 10. 3. The face labeled '9' (top) is opposite to the face labeled '9' (bottom-left). * This pair confirms the "equal values" condition as 9 = 9. **Calculation steps (derived from the problem and implied relationships):** 1. From 2x = 8, solve for x: x = 4. 2. From y = 10, y is already known. 3. Calculate x + y: x + y = 4 + 10 = 14.