Question

The length of a rectangle is 3 times its width and the length of its diagonal is 6√10 cm. Find its perimeter

Answer 1

Let the breadth be 'x'm

Length is equal to three times breadth=3x

Perimeter=84m

2(l+b)=84m

2(3x+x)=84

2(4x)=84

4x=84/2

4x=42

x=42/2

x=10.5

Therefore length=3x=3(10.5)=31.5m

Breadth=x=10.5m

Answer 2

hey here is your answer

Let the width be x.

Then, length is 3x

=>
Diagonal =√(l^2+b^2)

=√(9x^2 + x^2)

=√(10x^2) = x√10

But, diagonal = 6√10 cm

Hence, 6√10=x√10

x=6 cm

Thus, perimeter = 3x+x = 4x = 4*6 = 24 cm

therefore, perimeter is 24cm