学习了角的知识后,张老师让大家画一个135°的角。只见欢欢拿出量角器,一边熟练地画着一边自信地说:“我先画一条射线,使量角器的中心与射线的端点重合,并且使量角器的零刻度线与这条射线重合,然后,从与这条射线重合的零刻度开始数,在量角器的135°刻度线的地方点上一个点,以画出的射线的端点为端点,通过刚刚画出的 After learning the knowledge of the corner, Zhang let everyone draw a 135 ° angle. I saw joy and come up with the protractor, while proficiently painting while confidently said: ”I first draw a ray so that the center of the protractor coincides with the end of the ray, and make the protractor coincide with the zero-scale line and this ray, and then , Counting from the zero scale coincident with this ray, a point is placed at the place of the 135 ° tick on the protractor, the end of the ray drawn is taken as the end point,