Addition 1: Easier solution: Select both lines, choose menu
Right, then choose menu
You can choose menu
Line instead of Connector.
To rotate the line, select the line and choose menu
Position and Size… (or just press
F4), and in the
Rotation tab give a value to
Edit 1: To move both end points: Choose menu
Points (or just press
F8), select both points of the line (
shift+click, or drag a selection frame around both points). Drag one point to join the other line.
Addition 2: No need to select both points, just drag the line to join the other.
To join both lines will be easier if
Snap to Object Border or
Snap to Object Points are active (to do that choose menu
Addition 3: After selecting both lines and choosing menu
Group, you can change individual format of each line. To do that: select the group, press
F3 (or choose menu
Enter Group), select one line, make your changes and press
Ctrl+F3 (or choose menu
Addition 4: Selecting both lines and choosing menu
Combine would convert both lines in a polygon. To partialy revert this, choose menu
Split (they will be no more lines, but polygons).
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