CBSE Class 10-Mathematics: Chapter –9 Some Applications of Trigonometry Part 8

Get top class preparation for CBSE right from your home: fully solved questions with step-by-step explanation- practice your way to success.

Question 10:

From a window (h m high above the ground) of a house in a street, the angles of elevation and depression of the top and foot of another house on the opposite side of the street are respectively, show that the height of the opposite house is

From a window of a house in a street

From a Window of a House in a Street

Loading image

Answer:

Let

In right

In right

Hence Proved.

Question 11:

A ladder rests against a wall at an angle to the horizontal. Its foot is pulled away from the wall through a distance ‘a’ so that it slides a distance ‘b’ down the wall making an angle with the horizontal. Show that

A ladder rests against a wall

A Ladder Rests Against a Wall

Loading image

Answer:

In right ,

Similarly, in right

Hence Proved.

Question 12:

A vertical tower stands on a horizontal plane and surmounted by vertical flagstaff of height h. At a point on the plane, the angles of elevation of the bottom and the top of the flagstaff are respectively, Prove that the height of the tower is

A vertical tower stands on a horizontal plane

A Vertical Tower Stands on a Horizontal Plane

Loading image

Answer:

Let Height of tower

Let Height of flagstaff

In right-angled triangle OAB and OAC,

And

Equating value of , we get