A 9m long ladder rests at 9m below a vertical wall. If the angle of elevation of the top of the wall from the foot of the ladderis 60°. Find the height of the wall.

Height of the wall is 27 m.

Explanation:

Let the height of the wall = h

Length of the ladder = 9 m

Angle of elevation = 60°

Ladder rests at 9 m below a vertical wall.

So, length of the wall upto which the ladder rests = h - 9

We know,

Cos Ф = base/ hypotenuse

cos 60° = length of the ladder / height of wall upto which the ladder rests

So,

h - 9 = 18

h = 27

Therefore, height of the wall is 27 m

it is a. 4.2 because 7.6-3.4 gets the remaining length of 4.2. i might be wrong but i am pretty sure this is the answer.

r and t.

both are 64 degrees.