Question

diagonal of a square is 20cm then find it's perimeter and area

Answer 1

if diagonal of square is 20cm
let each side be x
using Pythagoras theoram we have
x²+x²= 20²
2x²= 400
x²= 200
x=10√2 cm

area = 1/2diagonal × diagonal
=1/2×20×20
=200cm²

perimeter = 4x
=4×10√2
=40√2cm

Answer 2

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We know that d=√2s 

Given diagonal = 20 cm 

=> s = 20/√2 cm

Therefore, perimeter of the square is 4s= 4 x 20√2 = 40√2   cm.

Area = d/2
A. = 20/2
A=10cm...

Hope it helps you
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