Question

find the area of. triangle with sides 13cm ,14cm,and 15cm

Answer 1

the area will be 84 sq. cm
as ATQ,

Let a = 13, b = 14 and c = 15. Then, s=12(a+b+c)s=12a+b+c=21

 (s- a) = 8, (s - b) = 7 and (s - c) = 6.

Area =[s(s−a)(s−b)(s−c)]*√ss-as-bs-c =(21×8×7×6)*√21×8×7×6 = 84 sq.cm   

Answer 2

The area of a triangle with different sides is {s(s-a)(s-b)(s-c)}^(1/2)
where a,b,c are the differnt sides and s is the semi perimetre i.e. (13+14+15)/2.cm
Hence the required answer is {21.(21-13).(21-14).(21-15)}^(1/2)=84sqrcm.