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1试题呈现本校九年级数学月考试卷中有这样一道选择题:题目如图1,四边形ABGH,四边形BCFG,四边形CDEF都是正方形.则∠ACH+∠ADH的值为().A.45°B.60°C.75°D.90°本题综合考查了相似三角形的判定与性质、正方形的性质以及勾股定理等核心知识.此题难度适中,运用数形结合、几何直观的思想得以解决.那么此类问题的深层结构是什么?能否举一反三?笔者
1 questions present this ninth grade math monthly exam papers have a multiple choice questions: the title shown in Figure 1, the quadrilateral ABGH, quadrilateral BCFG, quadrilateral CDEF are square, then ∠ACH + ∠ ADH value () .A.45 ° B .60 ° C.75 ° D.90 ° This question examines the core knowledge of the judgment and properties of similar triangles, the properties of squares, and the Pythagorean theorem. This question is moderately difficult to solve using the combination of geometry and intuition. So what is the deep structure of such problems? Could I give top priority to the author?