Question

the diagonal of a square 12cm long . find its area and perimeter​

Answer 1

Area of square = 1/2 (d)²

= 1/2 (12)²

= 1/2 × 12 × 12

= 72

Side of a square = √Area

= √72

= √(2 × 2 × 2 × 3 × 3)

= 2 × 3√2

= 6 × 1.41

= 8.46 cm

Perimeter of square = 4 × 8.46 = 33.84 cm

Answer 2

Answer:

area of square = 72 cm² ; perimeter of a square= (48/$\sqrt{2}$ )cm

Step-by-step explanation:

given that:

diagonal of a square = 12cm

we know that ;

all sides of a square are equal

let the side of a square be 'S'

from pythagoras theorem ; diagonal² = side² + side²

substitute the value of diagonal = 12 cm in [diagonal² = side² + side²]

(12)(12)cm² = S² +S²

144cm² = 2S²

S² = 72 cm²

S = 12/$\sqrt{2}$ cm

so area of square = side² = S²

area of square = 72 cm²

perimeter = 4(side)

perimeter of a square= 4(12/$\sqrt{2}$ )cm = (48/