Question

the perimeter of a square is 56 cm. what is the approximate length of its diagonal? 10.6 cm 14.0 cm 15.0 cm 19.8 cm

Answer 1

The answer to this problem is 19.8

Answer 2

we know that

`Perimeter\ of\ a\ square=4b`

where

b is the length side of a square

Step
`1`

Find the length side b of a square

`P=56cm\\ P=4b\\ 56=4b\\ b=56/4\\ b=14cm`

Step
`2`

Find the length of the diagonal of a square

Applying the Pythagorean Theorem

`D=\sqrt{b^(2)+b^(2)} \\ D=\sqrt{14^(2)+14^(2)}\\ D=14√(2) cm\\ D=19.80cm`

therefore

the answer is

`19.80cm`