Question

One sees the top of a tree on the bank of a river at an elevation of 70° from the other bank. Stepping 20 meters back, he sees the top of tree at an elevation of 55° .Height of the person is 1.4 metres.
(a) Draw a rough figure and mark the measurements.
(b) Find the height of the tree.
(c) Find the width of the river.(tan 70°=2.75 ; tan 55°=1.43).

Answer 1

(a) Drawn

(b) tan 70° = AO/OF

→ 2.75 = AO/OF → 2.75 OF = AO

tan 55° = AO/OE

→ 1.43 = AO/(OF + FE)

→ 1.43 OF + 1.43 FE = AO

→ 1.43 OF + 1.43(20) = 2.75 OF

→ 28.6 = 1.32 OF

→ 21.7 m = OF [Length of River (iii)]

→ AO = 2.75 × 21.7 m

→ AO = 59.6 m

Total Length of Tree = (59.6 + 1.4)m

→ 61 m (ii)

Answer 2

Answer:

Step-by-step explanation: