Length of the fence of a trapezium shaped field ABCD is 120 m. If BC = 48 m, CD = 17 m and AD = 40 m, find the area of this field. Side AB is perpendicular to the parallel sides AD and BC
If a perpendicular from D to BC is drawn then it will be equal to AB,
then EC = 48-40 = 8 m.
In ΔDEC DE2 = DC2-EC2
DE2 = 172 - 82 = 289 - 64 = 225
Or, DE = 15 m
Area of Trapezium = 1/2 × (sum of parallel sides) × height
= 1/2 × (48 + 40) × 15
= 660 m2