Question

Find the perimeter of the rectangle whose length is $40cm$ and a diagonal is $41cm$.

Answer 1

Given that length of the side of the rectangle is $l=40cm$ and

the length of the diagonal is $d=41cm$

let breadth be $bcm$

Therefore, $l^2+b^2=d^2$

$⟹{40}^2+b^2={41}^2$

$⟹b^2=81$

$⟹b=9cm$

we know that the perimeter of the rectangle is $2(l+b)=2(40+9)=98cm$