A = sqrt{s(s-a)(s-b)(s-c)}
s={a+b+c}/{2}.
s = (7.2+6.7+4.5)/2 = 18.4/2 =9.2
A =sqrt (9.2 *(9.2-7.2) *(9.2-6.7) * (9.2-4.5) )
=sqrt( 9.2*2*2.5*4.7)
= sqrt(216.2)
=14.7
Choice C
9.5m questions
12.2m answers