You can insert line segments in Microsoft Office Word 2013 using the Equation tool. In math, a line segment is a part of an infinite line bounded by two points. The line segment is represented by the two endpoints of the segment and a horizontal bar over the two letters. For example, if your line segment is bounded by points "A" and "B," the line segment would be represented by an overbar over "AB." Word includes all the necessary tools for writing and editing equations, so you don't need to install any third-party add-ons. Note that older versions of Microsoft Word can't edit equations created in Word 2013.
Inserting Line Segments
Open the document you want to edit in Microsoft Word 2013 and then locate the "Equation" tool in the Symbols group on the Insert tab. Click the "Equation" button to insert a new equation into the document. The Design Equation Tools tab is displayed automatically on the ribbon, with the Design tab selected by default. Click the "Accent" button in the Structures group and choose the "Bar" accent. The accent's icon is the only one with a single overbar. Click inside the box that appears inside the equation box and type the two endpoints of the line segment. Note that points are usually represented by capital letters. Click outside of the equation box to finish editing the equation, and press "Ctrl-S" to save the changes.