Q18 of 45 Page 11

Find the area of a rhombus, each side of which measures 20 cm and one of whose diagonals is 24 cm.

Given: Side = 20 cm


Diagonal = 24 cm


To find: Area of rhombus


Formula Used:


Area of rhombus = 1/2 × d1 × d2


Explanation:



Length of side of rhombus = 20 cm


Length of one diagonal = 24 cm


In ΔAOB


Using Pythagoras theorem:


AB2 = OA2 + OB2


202 - 122 = OB2


OB2 = 400 – 144


OB2 = 256


OB = 16


Hence, length of another diameter = 16 × 2 = 32 cm


Area of rhombus =


Area of rhombus =


Area of rhombus = 384 cm2


More from this chapter

All 45 →
16

The height of a right circular cylinder is 10.5 cm. If three times the sum of the areas of its two circular faces is twice the area of the curved surface area. Find the radius of its base.

 17

The floor of a building consists of 3000 tiles which are rhombus shaped and each of its diagonals are 45 cm and 30 cm in length. Find the total cost of polishing the floor, if the cost per m2 is Rs. 4.

 19

A classroom is 11 m long, 8 m wide and 5 m high. Find the sum of the areas of its floor and the four walls (including doors, windows etc.)

 20

A cuboid has total surface area of 50 m2 and lateral surface area as 30 m2. Find the area of its base.