Tip to Tail Method

Click and drag at the head and tail of blue vectors to change the magnitude and direction of the vectors. Click and drag at the blue vectors to move the vectors. To move the red vector, click and drag at the vector head. The red vector is always the resultant of the two blue vectors.
1. Arrange the blue vectors such that the tail of one vector is touching the head of another. 2. Drag the red vector such that it forms a triangle together with the other blue vectors. 3. Repeat steps 1 and 2 using different blue vectors. Is it always possible to form a triangle?