The length of a rectangle is thrice its breadth and the length of its diagonal is 8√10 cm. The perimeter of the rectangle is

Question

Philoid · Accepted Answer

Given: Length of rectangle (l) = 3 × breadth(b) = 3b

Diagonal of rectangle = 8√10 m

We know that,

Base² + Perpendicular² = Hypotenuse²

⇒ b² + (3b)² = (8√10) ²

⇒ b² + 9b² = 640

⇒ 10b² = 640

⇒ b² = 64

⇒ b = 8 cm

Therefore,

l = 3b = 24 cm

Hence,

Perimeter of a rectangle = 2(length + breadth)

= 2(24 + 8)

= 64 cm