Level 7: Construct a line segment with the same length and same direction as line segment AB but with begin point C.

Hint: Think parallelogram

Solution: Suppose we have the required line CD, join BD, then ABDC must be a parallelogram. Using the parallel line tool in level 6. We can easily construct this parallelogram by first constructing a line at B parallel to AC, and then a line at C parallel to AB, the new intersection point D is the parallelogram point.