Question

The diagonal of the rectangle is $13$ cm whose width is $12$ cm. Find its length.

• A. $4$ cm
• B. $5$ cm
• C. $6$ cm
• D. $7$ cm

Answer 1

The correct option is B $5$ cm

We know, square of diagonal in a rectangle $=$ $l^2+w^2$
$\Rightarrow {13}^2=l^2+{12}^2$
$\Rightarrow {13}^2=l^2+{12}^2$

$\Rightarrow 169-144=l^2$
$\Rightarrow l^2=25$
$\Rightarrow l=5$ cm