Question

11. What will be the perimeter of a rectangle if its length is 3 times its width and the length of the
diagonal is 8 ×root 10 cm?
(A) 16/10 cm (B) 15/10 cm (e) 64 cm
(D) 24/10 cm​

Answer 1

Answer:

Step-by-step explanation:

Options wrong hai.

Answer 2

The perimeter of the rectangle is 64 cm. (option c)

• Given data :

Length of the rectangle = 3× Width of the rectangle

Length of the diagonal of the rectangle is 8✓10 centimetres.

• Let,the width of the rectangle = x centimetres ( Assume x as a variable to calculate the value of the perimeter of the rectangle)

• So,the length of the rectangle

= 3×x

= 3x cm

• Now,we have to calculate the length of the diagonal of the rectangle by using the following mathematical formula :

= ✓(length)²+(width)²

= ✓(3x)²+(x)²

= ✓10x² cm

• Now, if we compare the value of the length of the diagonal that we have calculated the value of the length of the diagonal is given in the question, then we will get the following equation :

✓10x² = 8✓10

10x² = 640 (squaring both side)

x² = 640/10

x² = 64

x = 8

So,the width of rectangle is 8 centimetres.

So,the length of the rectangle will be

= 8×3

= 24 cm

• At last,we have to calculate the perimeter of the rectangle by using the following mathematical formula

= 2×(length + breadth)

= 2× (24+8)

= 2×32

= 64 cm (answer)