【教学目标】了解余角和补角的概念,知道余角和补角的性质,能运用它们进行简单的说理,并能解决简单的实际问题.【教学重、难点】教学重点:余角和补角的概念和性质.教学难点:通过“观察、操作一猜想、探索”过程, Teaching Objectives To understand the concept of extra corners and supplementary angles, to know the characters of extra corners and supplementary angles, to use them for simple reasoning and to solve simple practical problems. The concept and nature of the supplementary angle. Difficulties in teaching: Through the “observation, operation of a guess, explore ” process,