Question

the perimeter of a square is 28 cm find the area and the length of its diagonal

Answer 1

Perimeter of square = 4×side
28 = 4×side
side = 28/4 = 7
Area of square = side × side = 7×7 = 49


Area of square = 1/2×(diagonal)²
49 = 1/2×(diagonal)²
Diagonal ² = 49×2 = 98
Diagonal = ✓98 = 9.8cm

Answer 2

Given in the question:

Perimeter of the square = 28 cm

Solution:

As we all know that square has all its sides equal in length.

So perimeter of square can be calculated by multiplying the length of side by 4

So by this method:-

4× length of side= 28 cm

So length of side = 28/4 = 7 cm

Area of square can be calculated by formula = length of side × length of side

= 7×7

=49 cm^2

Another Formula of area of square= 1/2 × (diagonal)^2

So, diagonal= √(49×2) = √98

Therefore, length of diagonal = √98 = 9.89 cm