Question

Please solve this ?

Answer 1

Given: Length of a diagonal= 20 cm

To find: Area of a square=?

Solution: Let the one side of a square be x cm.

So, all the sides of a square will be x cm.

According to question, we have

Making a single diagonal in a square will make 2 right angled triangles.

Thus for 1 right angled triangle we get:

P^2+B^2= H^2 (Pythagorus theorem)

As P=B= x cm. So we have as shown:

x^2+x^2=20^2; 2x^2=20×20; 2x^2=400

Therefore, x^2=400/2; x^2=200; so x=(200)^1/2

Hence, x=(100×2)^1/2=(100)^1/2×(2)^1/2=10×(2)^1/2 or 10 root 2.

Thus all the sides of a square is 10 root 2.

Finally, Area of a square= (side)^2=

(10 root 2)^2=10^2×(root 2)^2=100×2= 200 cm^2. Answer.

Answer 2

Answer:

Area of square= d^2/2

'd' is diagonal

therefore, 20×20/2

= 200cm. square

area of square= side×side

2000. = side^2

side= √200

therefore, length of square = 14.14