Question

Two parallel sides of a trapezium are 60 m and 77 m and the other sides are 25 m and 26 m find the area

Answer 1

ANSWER

Draw a line BC parallel to AD 

Draw a perpendicular line BE on DF

ABCD is a parallelogram.

BC=AD=25 cm

CD=AB=60 cm

CF=77−CD=17cm

For ΔBCF

semiperimeter of triangle=225+26+17

                                          

                                          =268=34

By Heron's Formula of triangle=s(s−a)(s−b)(s−c)

 =34(34−25)(34−26)(34−17)

                                                   =204cm²

Also, area of ΔBCF=21×base×height

204=21BE×CF

204=21BE×17

BE=408/17

BE=24 cm

Area of Trapezium=21(AB+DF)×BE

=1/2(60+77)×24

Area=1644cm²