The perimeter of the quadrangle is 98m9dm, side AB is 26m5dm, BC is 15m, CD is 28m3dm.

The perimeter of the quadrangle is 98m9dm, side AB is 26m5dm, BC is 15m, CD is 28m3dm. Find the length of the AD side.

Given:
The perimeter of the quadrilateral ABCD is 98 meters 9 decimeters.
The AB side is 26 meters 5 decimeters.
The side of the sun is 15 meters.
The CD side is 28 meters 3 decimetres.

Let’s convert meters to decimeters:
1 m = 10 dm.
AB = 265 dm.
BC = 150 dm.
CD = 283 dm.
The perimeter is 989 dm.

Find the AD side:
989 – 265 – 150 – 283 = 291 dm.
Answer: the AD side is 291 decimetres.