探究开放型问题,由于仅仅已知某些条件,结论目标不明确,往往问题变得扑朔迷离;开放型问题因其潜在的魅力,在中考试题的题型中有着广泛的分布.等腰直角三角形与等边三角形都具有多种性质,在两类三角形内过角的顶点引射线构造特殊角,通过引垂线构造线段,线段之间往往有特殊关系.下面结合两类 Exploring the open-type problem, the open-ended question has a wide distribution in the questions of the middle-school exam questions due to its potential attractiveness because only certain conditions are known and the conclusion is not clear. Equilateral triangles have a variety of properties, in the two types of triangles within the corner of the top of the erect ray special angle, the construction of the line segment by introducing vertical lines, there is often a special relationship between the line segments. The following combination of two types