Câu 1 :

program tam_giac;
uses crt;
var a, b, c, cv, h, s : real;
begin
clrscr;
write('nhap do dai canh a :');readln(a);

write('nhap do dai canh b:');readln(b);

write('nhap do dai canh c :');readln(c);
write('nhap do dai chieu cao h :');readln(h);

cv := a + b + c;
s := 0.5*a*h;

writeln('chu vi tam giac la :', cv:3:2);
writeln('dien tich cua tam giac la :', s:3:2);
readln
end.

Câu 2 :

program hinhchunhat;
var a, b, s, c: real;
begin
write('chieu dai hinh chu nhat la :');readln(a);
write('chieu rong cua hinh chu nhat la :');readln(b);
s := a*b;
c :=(a+b)*2;
writeln('dien tich hinh chu nhat la :', s);
writeln('chu vi hinh chu nhat la :', c);
readln
end.

Câu 3 :

Program Hinh_tron;
Uses crt;
Var r, cv, dt : real;

const pi = 3.14;

Begin
Clrscr;
Write ('Nhap ban kinh hinh tron: ');
Readln (r);
cv := 2*pi*r;
dt := r*r*pi;
Writeln('Chu vi hinh tron la : ', cv);
Writeln('Dien tich hinh tron la :', dt);
Readln
End.

bài 2:

program bai_giai;

uses crt;

var a,b,c,h:longint;dt,ch:real;

begin

clrscr;

write('nhap canh a :');readln(a);

write('nhap canh b:');readln(b);

write('nhap canh c :');readln(c);
write('nhap chieu cao h :');readln(h);

if(a+b>=c)and(a+c>=b)and(b+c>=a)then 

begin

cv:=a+b+c;

dt:=a*h/2;

writeln('chu vi:=',cv);

write('dien tich:=',dt);

end else write('ba canh a,b,c khong la hinh tam giac');

readln;

end.

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bài 3:

program bai_giai;

uses crt;

var a,b,cv,dt:longint;

begin 

clrscr;

write('nhap chieu dai cua hinh chu nhat:');readln(a);

write('nhap chieu rong cua hinh chu nhat:');readln(b);

cv:=(a+b)*2;

dt:=a*b;

writeln('chu vi:=',cv);

write('dien tich:=',dt);

readln;

end.

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bài 4:

program bai_giai;

uses crt;

var r:lognint;cv,dt:real;const pi=3.14;

begin

clrscr;

write('nhap ban kinh hinh tron:');readln(r);

cv:=r*2*pi;

dt:=r*r*pi;

writeln('dien tich:=',dt);

write('chu vi:=',cv);

readln;

end.