等腰三角形有两边相等、两底角相等、“三线合一”、轴对称等重要性质.等腰三角形有可能是钝角三角形,直角三角形,锐角三角形.等边三角形也是等腰三角形.等腰三角形底边上的高线所在的直线是这个等腰三角形的对称轴,对称轴两侧的部分可以完全重合.利用等腰三角形的轴对称性,可以达到“挪动”线段、角等的目的. Isosceles triangle has the same two sides, two bottom angles are equal, “three line one ”, axisymmetry and other important properties .Isostagonal triangle may be obtuse triangle, right triangle, acute triangle. Isosceles triangle is also isosceles triangle. The line where the high line on the bottom of the waist triangle is located is the axis of symmetry of this isosceles triangle, and the sections on both sides of the symmetry axis are completely coincident. Using the symmetry of the isosceles triangle, lines, angles, etc. can be reached the goal of.