Given:
Perimeter of parallelogram = 50 inches
Length of one side is 15 inches
Find the length of the adjacent side.
Parallelograms have 4 sides and its measures of opposite sides are equal.
Perimeter = 2a + 2b
where:
a are opposite sides of equal measure
b are opposite sides of equal measure
50 inches = 2(15 inches)
50 inches = 30 inches + 2b
50 inches - 30 inches = 2b
20 inches = 2b
20 inches / 2 = b
10 inches = b
The length of the adjacent side is 10 inches.