三角形的高、中线和角平分线是三角形中三种重要的线段,它们对我们研究三角形的一些特征会有很大的作用.我们需要从不同的角度认识这三种线段.例1小华在电话中问小明:“已知一个三角形的三边长分别为4,9,12,如何求这个三角形的面积?”小明提示说:“可通过作最长边上的高来解.”那么,根据小明的提示作出的正确图形是(). The triangle’s high, midline, and angle bisectors are the three important line segments in the triangle. They have a great effect on the characteristics of the triangles we study. We need to understand these three line segments from different perspectives. Example 1 Xiaohua The phone asks Xiao Ming: “ Knowing a triangle’s three sides length is 4, 9, 12 respectively, how to ask the area of ​​this triangle?” Xiao Ming prompts to say: “ can be solved by making the longest side high. ”Then, the correct graphic made according to Xiaoming’s hint is ().