Question

find the area of the triangle whose sides are 9cm , 12cm , and 15cm .
using herons formula

Answer 1

Answer:

According to the herons formula

area of a triangle=√s(s-a)(s-b)(s-c). [where s=(a+b+c)/2 and a,b,c are the sides]

9+12+15=36cm

s=36/2

s=18cm

area=√s(s-a)(s-b)(s-c)

=√18*(18-9)*(18-12)*(18-15)

=√2916

=54cm^2

Answer 2

Answer:

Area of a triangle ( Heron's Formula )

Step-by-step explanation:

a = 9cm

b = 12cm

c = 15cm

s = ( a+b+c )÷ 2

s = ( 9 + 12 + 15 ) ÷ 2

s = ( 36 ) ÷ 2

s = 18 cm

By Using Heron's Formula,

Area of a triangle = √s (s-a) (s-b) (s-c)

Area of the given triangle = √ 18 ( 18-9 ) ( 18-12 ) ( 18-15 )

                                           = √ 18 ₓ 9 ₓ 6 ₓ 3

                                           = √ 2916

                                           = √ 54cm∧2