Geometrical Constructions (Exercise 19.4) RD Sharma Solutions | Mathematics (Maths) Class 6 PDF Download

 Page 1


 
 
 
 
 
 
                                                                              
1. Construct the following angles with the help of a protractor: 
45
o
, 67
o
, 38
o
, 110
o
, 179
o
, 98
o
, 84
o
 
Solution: 
 
Construct a ray OA. 
Now place the protractor on the ray OA such that its centre coincides with point O and the diameter coincides 
with OA. 
Mark a point B against the mark of 45
o
 on the protractor. 
Remove the protractor and construct the line OB where ?AOB is the required angle. 
 
In the same way draw the angles 67
o
, 38
o
, 110
o
, 179
o
, 98
o
 and 84
o
 
Page 2


 
 
 
 
 
 
                                                                              
1. Construct the following angles with the help of a protractor: 
45
o
, 67
o
, 38
o
, 110
o
, 179
o
, 98
o
, 84
o
 
Solution: 
 
Construct a ray OA. 
Now place the protractor on the ray OA such that its centre coincides with point O and the diameter coincides 
with OA. 
Mark a point B against the mark of 45
o
 on the protractor. 
Remove the protractor and construct the line OB where ?AOB is the required angle. 
 
In the same way draw the angles 67
o
, 38
o
, 110
o
, 179
o
, 98
o
 and 84
o
 
 
 
 
 
 
 
 
 
2. Draw two rays PQ and RS as shown in Fig. 19.14 (i) and (ii). Using protractor, construct angles of 15
o
 
and 138
o
 with one arm PQ and RS respectively. 
 
Solution: 
 
(i) Construct a ray PQ as given in the question. 
Now place the protractor on PQ such that its centre coincides with the point P and the diameter coincides with 
PQ. 
Mark B against the mark of 15
o
 on the protractor. 
Construct PB by removing the protractor. 
 
Page 3


 
 
 
 
 
 
                                                                              
1. Construct the following angles with the help of a protractor: 
45
o
, 67
o
, 38
o
, 110
o
, 179
o
, 98
o
, 84
o
 
Solution: 
 
Construct a ray OA. 
Now place the protractor on the ray OA such that its centre coincides with point O and the diameter coincides 
with OA. 
Mark a point B against the mark of 45
o
 on the protractor. 
Remove the protractor and construct the line OB where ?AOB is the required angle. 
 
In the same way draw the angles 67
o
, 38
o
, 110
o
, 179
o
, 98
o
 and 84
o
 
 
 
 
 
 
 
 
 
2. Draw two rays PQ and RS as shown in Fig. 19.14 (i) and (ii). Using protractor, construct angles of 15
o
 
and 138
o
 with one arm PQ and RS respectively. 
 
Solution: 
 
(i) Construct a ray PQ as given in the question. 
Now place the protractor on PQ such that its centre coincides with the point P and the diameter coincides with 
PQ. 
Mark B against the mark of 15
o
 on the protractor. 
Construct PB by removing the protractor. 
 
 
 
 
 
 
 
Here ?QPB is the required angle of 15
o
. 
 
(ii) Construct a ray RS as given in the question. 
Now place the protractor on RS such that its centre coincides with the point R and the diameter coincides with 
RS. 
Mark T against the mark of 138
o
 on the protractor. 
Construct ST by removing the protractor. 
 
Here ?RST is the required angle of 138
o
.