Program Example3;uses Crt;vara,b,c,P,S :real;beginwrite('Nhap vao 3 canh : '); readln(a,b,c);If (abeginP:=(a+b+c)/
2;S:=sqrt(p*(p-a)*(p-b)*(p-c));writeln('3 canh ban vua nhap la 3 canh cua 1
tam giac.');writeln('chu vi cua
tam giac la : ',P*
2:4:
2,' cm');writeln('die[r]