program dtandkt;

uses crt;

var a,b,h,d1,d2:real;

begin

clrscr;

write('Nhap day be: ');   readln(a);

write('Nhap day lon: ');   readln(b);

write('Nhap chieu cao: ');   readln(h);

write('Nhap duong cheo thu nhat: ');   readln(d1);

write('Nhap duong cheo thu hai: ');   readln(d2);

writeln('Dien tich hinh thang do la: ',((a+b)*h/2):2:2);

if d1=d2 then write('Day la hinh thang can')

  else write('Khong phai hinh thang can: ');

readln

end.

program ct;

uses crt;

var a,b,h,S:integer;

begin

clrscr;

writeln('Nhap do dai hai day: '); readln(a,b);

writel('Nhap chieu cao: '); readln(h);

S:=h*((a+b)/2);

writeln('Dien tich hinh thang do la: ',S); readln;