Question

the diagonals of rhombus are 15 cm and 20 cm what is its area find also if perimeter

Answer 1

Answer:

Given ,

Diagonals of a rhombus = 15cm x 20cm

Therefore area of rhombus = 1/2xDiagonal 1 x diagonal 2

=1/2x15x20

=150cm square.

Answer 2

Given,

• The diagonals of a rhombus are 15 cm and 20 cm.

To find,

• The area of the rhombus
• The perimeter of the rhombus

Solution,

The diagonals of a rhombus are 15 cm and 20 cm then the area is 150 cm² and its perimeter is 50 cm.

We can simply find the area of the Rhombus by using the formula of area of Rhombus,

Area of rhombus = 1/2 * d1 * d2

                            = 1/2 * 15 * 20

                            = 150 cm²

Now, for finding the perimeter of the Rhombus, we have to find the side of the rhombus.

As we know the diagonals of the rhombus bisect each other at the right angle.

Using Pythagoras theorem,

            $(H)^2 = (B)^2 + (P)^2$

where H is the side of the rhombus and B and P are the diagonals of the rhombus.

As the diagonals of the rhombus bisect each other, then

B = 15/2 cm and P = 10 cm    

              $(H)^2 = 225/4 + 100$

              $(H)^2 = 625/4$

             $(H) = 25/2$ cm

Side of the Rhombus = 25/2 cm

Now, the perimeter of the rhombus = 4* side  

                                                              = 4 * 25/2

                                                              = 50 cm

Hence, the diagonals of a rhombus are 15 cm and 20 cm then the area is 150 cm² and its perimeter is 50 cm.