Let a rectangular field ABCD
A/Q a man cross rectangular field diagonally and he had to walk 20m
So,Diagonal of Rectangle =20m
Length=16m (given)
We know that Each angle of a rectangle is 90°
ADC forms a right angled triangle
AC=16m(perpendicular)
AD=20m(Hypotenus)
CD=?(base)
According to Pythagorean Theorem
h2=b2+p2
(20)2=b2+(16)2
400=b2+256
b2=144
b=√144
b=12m