You can move the endpoints of a line object, but it requires using a combination of Horizontal Position, Vertical Position, Width and Height. This can get a bit complicated, and if the line requires a change in slope then a second line object must be created and visibility used to choose between them.
(The Height animation cannot go negative, so when the slope goes through zero, you must make the positive sloping line dissappear and make a negative sloping line appear and control it's height and position)
I have done this for a single line, but I would dread even thinking about trying to do it for a multitude of lines.