Selina Concise Mathematics Class 9 ICSE Maths Solutions Chapter 24 - Solution of Right Triangles

Selina Concise Mathematics Class 9 ICSE Solutions Solution of Right Triangles

Selina ICSE Solutions for Class 9 Maths Chapter 24 Solution of Right Triangles [Simple 2-D Problems Involving One Right-angled Triangle]

Exercise 24

1.Find 'x' if:

(i)

(ii)

(iii)

Solution 1:

2.Find angle 'A' if:

(i)

(ii)

(iii)

Solution 2:

3.Find angle 'x' if:


Solution 3:

4.Find AD, if:

(i)

(ii)

Solution 4:

5.Find the length of AD.

Given: ABC = 60^o.

DBC = 45^o

And BC = 40 cm.

Solution 5:

6.Find the lengths of diagonals AC and BD. Given AB = 60 cm and BAD = 60^o.

Solution 6:

7.Find AB.

Solution 7:

Thus AB = AC + CD + BD = 54.64 cm.

8.In trapezium ABCD, as shown, AB // DC, AD = DC = BC = 20 cm and A = 60^o. Find:

(i) length of AB

(ii) distance between AB and DC.

Solution 8:

First draw two perpendiculars to AB from the point D and C respectively. Since AB|| CD therefore PMCD will be a rectangle.
Consider the figure,

9.Use the information given to find the length of AB.

Solution 9:

10.Find the length of AB.

Solution 10:

11.In the given figure, AB and EC are parallel to each other. Sides AD and BC are 2 cm each and are perpendicular to AB.

Given that AED = 60^o and ACD = 45^o. Calculate:

(i) AB(ii) AC(iii) AE

Solution 11:

12.

Solution 12:

13.Find

(i) BC

(ii) AD

(iii) AC

Solution 13:

14.In right-angled triangle ABC; B = 90^o. Find the magnitude of angle A, if:

(i) AB is times of BC.

(ii) BC is times of AB.

Solution 14:

15.A ladder is placed against a vertical tower. If the ladder makes an angle of 30^o with the ground and reaches upto a height of 15 m of the tower; find length of the ladder.

Solution 15:
Given that the ladder makes an angle of 30o with the ground and reaches upto a height of 15 m of the tower which is shown in the figure below:

16.A kite is attached to a 100 m long string. Find the greatest height reached by the kite when its string makes an angles of 60o with the level ground.

Solution 16:

17.Find AB and BC, if:

(i)

(ii)

(iii)

Solution 17:

18.Find PQ, if AB = 150 m, P = 30^o and Q = 45^o.

(i)

(ii)

Solution 18:

19.If tan x^o =,

tan y^o = and AB = 48 m; find the length of CD.

Solution 19:

20.The perimeter of a rhombus is 96 cm and obtuse angle of it is 120^o. Find the lengths of its diagonals.

Solution 20:

We also know that in rhombus diagonals bisect each other perpendicularly and diagonal bisect the angle at vertex.
Hence POR is a right angle triangle and

Selina Concise Mathematics Class 9 ICSE Maths Solutions Chapter 24 - Solution of Right Triangles