To Create Lines
1. On the Design tab, click the arrow next to Line and then choose a creation method:
◦ Click
Single and select the start point of the line.
◦ Click
Tangent and select an arc or circle at the point of tangency to set the start point of the line.
When you select a creation method, the location of the start point is displayed, relative to the base point.
2. Rubberband the pointer and select a second point to size the line.
|  Use the dimensions mini toolbar to assign explicit values to the line length and position. |
3. To lock the one of the dimensions of the entity you are creating, press Enter or type L. Press Tab to switch to the other dimensions.
4. When creating a line chain, continue selecting more points as needed.
5. Middle-click to exit the tool.