FRANK Solutions for Class 9 Maths Chapter 20 - Constructions of Quadrilaterals

Chapter 20 - Constructions of Quadrilaterals Exercise Ex. 20.1

Question 1

Solution 1

Question 2

Solution 2

Question 3

Solution 3

Question 4

Solution 4

Question 5

Solution 5

Question 6

Solution 6

Question 7

Solution 7

Question 8

Solution 8

Question 9

Solution 9

Question 10

Solution 10

Question 11

Solution 11

Question 12

Solution 12

Question 13

Solution 13

Question 14

Construct a rectangle ABCD, when

AD = 3.2cm and diagonal BD = 5.5cm. Measure CD.

Solution 14

Steps of construction:

1. Draw AD = 3.2 cm
2. Draw ∠XAD = 90°.
3. With D as centre and radius BD = 5.5 cm, draw an arc to cut AX at point B.
4. Join BD.
5. With B as centre and radius 3.2 cm draw an arc and with D as centre and radius = AB, draw another arc to cut the previous arc at C.
6. Join BC and CD.

Thus, ABCD is the required rectangle.

CD = 4.5 cm

Question 15

Construct a rectangle ABCD, when

AB = 5cm and BC = 6.2cm.

Solution 15

Steps of construction:

1. Draw BC = 6.2 cm
2. Through B, draw BP such that ∠B = 90°
3. From BP, cut BA = 5 cm
4. With A and C as centres and radii 6.2 cm and 5 cm respectively, draw arcs cutting each other at D.
5. Join AD and CD.

Thus, ABCD is the required triangle.

Question 16

Solution 16

Question 17

Solution 17

Question 18

Solution 18

Question 19

Construct a rectangle PQRS, when its

Area = 21 cm² and length = 4.2cm

Solution 19

Since area of rectangle = 21 cm²

And, length = 4.2 cm

Breadth = Area ÷ Length = 21 ÷ 4.2 = 5 cm

Steps of construction:

1. Draw BC = 5 cm
2. Through B, draw BP such that ∠B = 90°
3. From BP, cut BA = 4.2 cm
4. With A and C as centres and radii 5 cm and 4.2 cm respectively, draw arcs cutting each other at D.
5. Join AD and CD.

Thus, ABCD is the required triangle.

Question 20

Construct a rectangle PQRS, when its

Area = 33.8cm² and breadth = 6.5cm

Solution 20

Since area of rectangle = 33.8 cm²

And, breadth = 6.5 cm

Length = Area ÷ Breadth = 33.8 ÷ 6.5 = 5.2 cm

Steps of construction:

1. Draw BC = 6.5 cm
2. Through B, draw BP such that ∠B = 90°
3. From BP, cut BA = 5.2 cm
4. With A and C as centres and radii 6.5 cm and 5.2 cm respectively, draw arcs cutting each other at D.
5. Join AD and CD.

Thus, ABCD is the required triangle.

Question 21

Solution 21

Question 22

Solution 22