Question

The adjacent sides of the rectangle are in ratio 3 : 9, if perimeter of rectangle is 48 cm, find length of diagonal.

• A. $10\sqrt{6}$
• B. $10\sqrt{12}$
• C. $6\sqrt{10}$
• D. None

Answer 1

Answer: (C)

$6\sqrt{10}$

Let the length of the rectangle $=9x$

Breadth of the rectangle $=3x$

Perimeter of the rectangle $=2(9x+3x)=48$

$\Rightarrow x=2$

Length of the diagonal $=\sqrt{{\left(9x\right)}^2+{\left(3x\right)}^2}$

$\Rightarrow$ Length of the diagonal $=6\sqrt{10}$