Answer:
12
Explanation:
A parallelogram has 4 sides. Opposite sides of a parallelogram are parallel and congruent.
Since one side has length p, its opposite side also has length p.
Since one side has length 17 ft, its opposite side also has length 17 ft.
The lengths of the 4 sides are p, p, 17 ft, and 17 ft.
The perimeter is the sum of the lengths of the sides, and it is 58 ft.
p + p + 17 + 17 = 58
2p + 34 = 58
2p = 24
p = 12