The tension will be greater if the line sags only a little.
Work Step by Step
The diagonal of a parallelogram represents the resultant, or sum, of the two vectors that are used to construct the parallelogram. This is discussed on page 29. Draw a parallelogram representing the 2 rope forces, where the upward resultant force is equal and opposite to the bird’s weight. Long vectors (i.e., large forces) for the parallelogram are needed when the clothesline sags only a little and the ropes are nearly horizontal.