The perimeter of a field in the shape of a rhombus is 116 m and one of its diagonals is 42 m. Its area is equal to the area of a rectangula…

Explanation

Side of rhombus = 29 m. The other half-diagonal = √(29² − 21²) = 20, so the other diagonal is 40 m and the area is ½ × 42 × 40 = 840 m². For sides 30k and 7k, 210k² = 840 gives k = 2, so the sides are 60 m and 14 m and the perimeter is 148 m.