NCERT Solutions for Class 9th Mathematics

Chapter 11 – CONSTRUCTIONS

(Complete Downloadable Chapter Solution PDF file is at the bottom of the page)

 

EXERCISE 11.1

 

1.  Construct an angle of 90° at the initial point of a given ray and justify the construction.

2.  Construct an angle of 45° at the initial point of a given ray and justify the construction.

3.  Construct the angles of the following measurements:

(i) 30°              (ii) 22 1/2°            (iii) 15°

4.  Construct the following angles and verify by measuring them by a protractor:

(i) 75°                          (ii) 105°                       (iii) 135°

5.  Construct an equilateral triangle, given its side and justify the construction.

 

EXERCISE 11.2

 

1.  Construct a triangle ABC in which BC = 7cm, ∠B = 75° and AB + AC = 13 cm.

2.  Construct a triangle ABC in which BC = 8 cm, ∠ B = 45° and AB – AC = 3.5 cm.

3.  Construct a triangle PQR in which QR = 6cm, ∠ Q = 60° and PR – PQ = 2cm.

4.  Construct a triangle XYZ in which ∠ Y = 30°, ∠ Z = 90° and XY + YZ + ZX = 11 cm.

5.  Construct a right triangle whose base is 12cm and sum of its hypotenuse and other side is 18 cm.