Find the diagonal of a square whose sides are 5cm long

5√2 cm or 7.1 cm

Step-by-step explanation:

We can use Pythagoras' Theorem:

The square on the diagonal is equal to the sum of the squares of the other two sides.

d² = 5² + 5²

d² = 25 + 25

d² = 50

d = √50

d = √ (25*2)

d = 5√2

d≈ 7.1 cm