Angles, front and center
Note: Problems 1.1–1.3 refer to the diagram below, triangle ABC.
1.1 Identify the sides and vertices of the triangle.
A triangle is a two-dimensional (or plane) figure that consists of three line segments intersecting only at their endpoints. Line segments are named according to the points at which they begin and end, so the sides of this triangle are . The vertices are the three points at which the segments intersect: A, B, and C.
These little bars look like line segments, which is why they appear ...