The sides of a triangular park are 200 m, 210 m and 290 m. The area of the park (in hectares)is:

As given in the question, a park of dimension 200m , 210m and 290m are shown in the figure above.

This is a right angle triangle as side are showing a triplet.

$$H^2=P^2+B^2$$

$$290^2=200^2+210^2$$

$$84100=40000+44100$$

$$84100=84100$$

$$L.H.S=R.H.S$$

Area of Right Triangle = $$\frac{1}{2}\times\ base\times\ height$$

= $$\frac{1}{2}\times\ 210\times\ 200$$

= 21000 $$m^2$$

1 hectare = 10000 $$m^2$$

Area = $$\frac{21000}{10000}=2.1\ hectares$$