Solution :
Distance between the foot of tree and the point of contact of the top of the tree on the ground = 6 cm.
Let the length of the remaining part be = h m.
Let the length of the broken part be = x m.
Angle made by the broken part with the ground = 30o.
From the figure
∴ Height of the tree = broken part + remaining part
= x + h = 2√ + 4√ = 6√ m