三角形是最基本的平面图形,三角板的形状是常见的直角三角形,以三角板为背景的求角问题是2011年各地中考数学热点题型,解决这类问题首先要了解三角板的构造:一个是等腰直角三角板,它的三个内角的度数分别是90°、45°、45°;另一个三角板三个内角的度数分别是90°、30°、60°。还要熟练掌握三角形的内角和定理和外角性质以及互余角、对顶角等概念。下面 Triangle is the most basic plane graphics, triangle shape is a common right triangle, triangular board as the background of the problem is around the corner in 2011 mathematics hot questions type, to solve these problems we must first understand the structure of the board: one is the isosceles Right angle triangle plate, the angle of the three inner angles are 90 °, 45 °, 45 °; the other three angles of the inner angles are 90 °, 30 °, 60 °. But also proficiency in the triangular interior and interior angles and theorems and the nature of the outer corner of each other, right angle and other concepts. the following