The length of a rectangle is 8 cm and each of its diagonals measures 10 cm. Find its breadth.

We know that a rectangle is a parallelogram in which every angle is a right angle.

Therefore, ∠ABC = 90^o

In ∆ABC,

AB² + BC² = AC²   [Pythagoras Theorem]

⇒ BC² = AC² − AB²

⇒ BC² = 10² − 8²

⇒ BC² = 100 − 64

⇒ BC² = 36

⇒ BC = 6 cm

Hence, breadth = 6 cm.