Question

From the top of a cliff the angles of depression of the top and the bottom of a tower 20mt. height were found to be 30°and 45°respectively. find the height of the cliff correct to 2 places of decimal.
plzzz help me with this if the answer will be correct I will mark u as a Brainliest.​

Answer 1

Answer:

let h be the height of the cliff and d be the distance between cliff and tower. Then

tan 45 = h/d

1=h/d

h=d ....(1)

tan30 = (h-20)/d

1/√3=(h-20)/d

d=√3(h-20) put d=h from (1)

h=√3h-20√3

√3h-h=20√3

h(√3-1)=20√3

h=20√3/(√3-1)=20√3(√3+1)/((√3-1)(√3+1))

=20√3(√3+1)/(3-1)=10√3(√3+1)

√3=1.733

h = 10×1.732×2.732 = 47.32 Ans