Question

9. The area of a square is 400cm^2
The length of its diagonal is​

Answer 1

Given

• Area of square = $400 {cm}^{2}$

To find:-

• Length of diagonal = ?

Find:-

As we know that,

$diagonal \: of \: square = \sqrt{2} \times side$

$area \: of \: square \: = {(side)}^{2}$

${(side)}^{2} = 400 {cm}^{2} \\ side = \sqrt{400 {cm}^{2} } = 20cm$

$diagonal = \sqrt{2} \times 20 = 20 \sqrt{2} cm$

Hope its help uh❤

Answer 2

Answer:

Hope my answer helps you mate ^_^

Step-by-step explanation:

Area of square is = side×side

Let side of square be X

400= X×X=X²

X=±20cm( as side cant be negative ignore it)

Now draw a diagnal in between square

to have 2 right triangle

in one Triangle

By Pythagoras theoram

(X) ²+(X)²=(D) ² (let diagnal be D)

400+400=(D) ²

D=20Root2

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