Question

If the length of the diagonal of a square is 20cm,then its perimeter must be
A) 40
B) 30
C) 10
D) 20

Answer 1

Hi ,

Let the side of the square = a cm

diagonal = d = √2 × a

According to the problem given,

d = 20cm

Therefore ,

√2 × a = 20

a = 20 / √2 cm

Perimeter of the square = 4a

= 4 × ( 20 / √2 )

Rationalize the denominator,

= ( 4 × 20 × √2 )/( √2 × √2 )

= ( 80√2 ) / 2

= 40√2 cm

I hope this helps you.

:)

Answer 2

answer is 40√2 mark as brain list