Tính diện tích tam giác với 3 cạnh

program dientich;

uses crt;

var a,b,c,p,s:real;

begin

clrscr;

write(‘Nhap a: ‘);   readln(a);

write(‘Nhap b: ‘);   readln(b);

write(‘Nhap c: ‘);   readln(c);

p:=(a+b+c)*0.5;

s:=sqrt(p*(p-a)*(p-b)*(p-c));

writeln(‘Dien tich tam giac la: ‘,s:2:2);

if s>50 then write(‘Lon hon dien tich hinh chu nhat’)

else if s=50 then write(‘Bang dien tich hinh chu nhat’)

     else if s<50 then write(‘Nho hon dien tich hinh chu nhat’);

readln

end.

*Tính diện tích bằng đường cao

program dientichl

uses crt;

var a,h,s:real;

begin

clrscr;

write(‘Nhap canh day: ‘);   readln(a);

write(‘Nhap duong cao: ‘);   readln(h);

s:=a*h*0.5;

writeln(‘Dien tich tam giac la: ‘,s:2:0);

if s>50 then write(‘Lon hon dien tich hinh chu nhat’)

else if s=50 then write(‘Bang dien tich hinh chu nhat’)

     else if s<50 then write(‘Nho hon dien tich hinh chu nhat’);

readln

end.

uses crt;

var a,b,c,h,s: real;

begin

writeln('Nhap canh a:');

readln(a);

writeln('Nhap canh b:');

readln(b);

writeln('Nhap canh c:');

readln(c);

if (a+b>c) and (a+c>b) and (b+c>a) then writeln ('Day la 3 canh cua tam giac') else writeln ('Day khong phai la 3 canh cua tam giac');

writeln('Nhap chieu cao h ung voi canh c:');

readln(h);

S:=(c*h)/2;

writeln('Dien tich tam giac do la:,s:5:2);

if S>50 then writeln('Dien tich tam giac lon hon dien tich hinh chu nhat') else

if S=50 then writeln('Dien tich tam giac bang dien tich hinh chu nhat') else

writeln('Dien tich tam giac nho hon dien tich hinh chu nhat');

readln;

end.