Question

Find the length of the side of a square if the length of its diagonal is 10 cm .​

Answer 1

The side of the square is  

5 √ 2

Explanation:

consider the triangle  A B C .

Now, Pythagoras' theorem tells us that

AB^2=AC^2 + CB^2

But  A B  and   B C  are both sides of the square, and then they both equal a certain quantity  , while  A C  is the diagonal and equals   10  cm. The previous identity becomes ;-

2D^2 = 100

D^2 =50

D =√50 =5√2