Bài 1

program CT;

Usescrt;

Var a,b,c :real;

Begin

Write('nhap a'): readln(a);

Write('nhap b'):readln (b);

Write ('nhap c'): readln(c);

Readln

End.

Bài 3

Program CT;

Usescrt;

Begin

Write (' nhap ba canh a,b,c') readln(a,b,c);

If(a+b<c)and (b+c<a)and (c+a<b) then writeln ('tam giac thuong');

If(a=b)and (b=c) then writeln ('tam giac deu');

If(a=b)and(b=c)and (c=a) then writeln ('tam giac can');

Readln

End.

Bài 4

Program CT;

Usescrt;

Var S,a,h:real;

Var CV,a,h:real;

Begin

Write('nhap a'): readln (a);

Write ('nhapb'):readln(b);

S:=(1/2)*(a*h);

CV:=a+h;

Write ('dien tich tam giac',S);

Write ('chu vi tam giac',CV);

Readln

End.

Program BTT;
Uses crt;
Var a,b,c,p,s: extended;
Begin
        Clrscr;
        Write('Nhap a,b,c: '); Readln(a,b,c);
        If (a+b>c) and (b+c>a) and (a+c>b) then
        Begin
                Write('Do la do dai 3 canh cua tam giac');
                If (sqr(a)+sqr(b)=sqr(c)) or (sqr(b)+sqr(c)=sqr(a)) or (sqr(a)+sqr(c)=sqr(b)) then
                Begin
                        Write('Tam giac vuong');
                        p:=(a+b+c)/2;
                        s:=sqrt(p*(p-a)*(p-b)*(p-c));
                        Writeln('Chu vi: ',2*p:0:2);
                        Write('Dien tich: ',s:0:2);
                End
                Else
                If (a=b) or (b=c) or (c=a) then Write('Tam giac can')
                Else
                If (a=b) and (b=c) then Write('Tam giac deu')
                Else Write('Tam giac thuong');
        End
        Else
        Write('Khong phai tam giac'); 
                Readln
End.