Question

Find the area of a triangle twi sides of which are 18 cm and 10 cm and the perimetre is 42 cm give the solution

Answer 1

area = √s(s-a) (s-b) (s-c)

s= 42/2 = 21cm

a= 18

b = 10

s = a + b + c

42 = 18 + 10 + c

c = 42 - 28 = 14cm

Area = √21(21-18) (21-10) (21-14)

        = √21 x 3 x 11 x 7

        =  21√11 cm²