Question

If the length of the diagonal of square is 10 cm, then the value of the side of the square is

• A. $15\sqrt{3}\text{cm}$
• B. $10\sqrt{2}\text{cm}$
• C. $5\sqrt{2}\text{cm}$
• D. $5\sqrt{3}\text{cm}$

Answer 1

The correct option is C

$5\sqrt{2}\text{cm}$

Let ABCD be the square
Let 'x' be the side of the square

Using Pythagoras' theorem,
$A{C}^2=A{B}^2+B{C}^2.(10{)}^2=x^2+x^{2}100=2x^2\Rightarrow x^2=50\Rightarrow x=\sqrt{50}=5\sqrt{2}\text{cm}$