A field in the form of parallelogram has sides 60m and 40m and one of its diagonals is 80m long. Find the area of parallelogram.
600√15 m2
s=AB+BC+AC2=1802=90 m
Area (ΔABC)
=√s(s−AB)(s−BC)(s−AC)
=√90(90−60)(90−40)(90−80)
=√90×30×50×10
=√1350000
=√15×90000
=300√15 m2
∴Area (ΔABCD)
=2×300√15=600√15 m2