Let ABCD be a rhombus of side 30m
AB=BC=CD=DA=30m
Also, diagonal=48m
BD=48m
Area of rhmbus=Area△ABD+Area△BCD
For △ABD,
Area of triangle=√s(s−a)(s−b)(s−c)
Here,s is the semi perimeter, and a,b,c are the sides of the triangle.
Here a=30m,b=30m and c=48m
S=a+b+c2=30+30+482=1082=54m
Area of △ABD=√s(s−a)(s−b)(s−c)
Here a=30m,b=30m ,c=48m and s=54,
=√54(54−30)(54−30)(54−48)=√54×24×24×6=432m2
Hence Area of △ABD=432m2
As both △ABD and △BCD have the same sides,
Area of △BCD=432 m2
So, Area of rhombus ABCD
= Area of △ABD + Area of △BCD=432+432=864m2
Thus, Area of Rhombus=864m2
Given that 18 cows to graze the field.
So, Area of 18 cows=Area of the rhombus.
Area of Each cow=Areaofrhombus18=86418=48m2
Thus, each cow will get 48m2 area of the grass field.