Question

Construct a rectangle ABCD in which AB = 4.8 cm and area is 12 cm².

Answer 1

Given: Rectangle ABCD with AB = 4.8 cm and area = 12 cm².

Step-wise calculation:

1. Area of a rectangle = AB × BC.

2. So, BC = Area ÷ AB

= 12 ÷ 4.8

3. Compute: 12 ÷ 4.8

= (12 × 10) ÷ (4.8 × 10)

= 120 ÷ 48

= 2.5

4. Therefore, BC = 2.5 cm.

Construction steps (ruler and compass or ruler and set-square):

1. Draw segment AB of length 4.8 cm.

2. At B erect a line perpendicular to AB.

3. With center B and radius 2.5 cm mark point C on that perpendicular so BC = 2.5 cm.

4. At A erect a line perpendicular to AB this is parallel to BC. With center A and radius 2.5 cm mark, point D on the perpendicular so that AD = 2.5 cm.

5. Join C to D. ABCD is the required rectangle AB || CD and BC || AD.

The other side BC and AD is 2.5 cm, so rectangle ABCD has sides 4.8 cm and 2.5 cm; constructed as above.