Question

A triangular park in a city has sides 37m ,20m and 51m.

(i) Find the cost of planting grass inside the park at the rate of ₹85

sq.m

(ii) Find the cost of fencing the park at the rate of ₹120 per metre​

Answer 1

A triangular park in a city has sides 37m ,20m and 51m.

(i) Find the cost of planting grass inside the park at the rate of ₹85

sq.m

(ii) Find the cost of fencing the park at the rate of ₹120 per metre

Answer 2

It form a scalen triangle so area = √{(s)(s-a)(s-b)(s-c)

s = (37+20+51)/2

= 108/2

= 54

a = 37

b = 20

c = 51

now

area = √{(s)(s-a)(s-b)(s-c)

= √{(54)(54-37)(54-20)(54-51)

= √{(54)(17)(34)(3)

= √93,636

= 306 m²

i) Find the cost of planting grass inside the park at the rate of ₹85

= 306 × 85

= ₹ 26010

ii)Find the cost of fencing the park at the rate of ₹120 per metre

perimeter = sum of all side

= 37+20+51

= 108 m

cost at ₹120 per metre

= 108 × 120

= ₹ 12960