第四十一课本课主题:平面上直线的相互位置,平行线定义本课主题Ⅰ.课外作业检查(在黑板上).Ⅱ.复习提问.已知底边,一底角及两腰之和,求作三角形,什么叫做公理、直线公理?Ⅲ.学习新教材.直线公理是说通过两点D与D_1可能且只能引一直线AB.假定仍通过此二点再引第二条直线A_1B_1时,则与第一 The forty-first lesson Theme of the lesson: The mutual position of the straight lines on the plane, the parallel lines define the subject of this lesson I. Check the homework assignment (on the blackboard). II. Review questions. Know the bottom edge, the bottom corner and the sum of the two waists , for the triangle, what is the axiom, linear axioms? III. learning new textbooks. Linear axioms is that through two points D and D_1 may and can only lead to a straight line AB. Assume that still through these two points and then cited a second line A_1B_1 When it is the first