VAR A,B,C,X1,X2:REAL;
PROCEDURE GPT(A,B,C:REAL);
VAR D:REAL;
BEGIN
D:=(B*B)/(4*A*C);
IF D<0 THEN BEGIN X1:=-1;X2:=-1 END
ELSE IF D=O THEN BEGIN X1:=-B/(2*A);X2:=-1; END
ELSE BEGIN
X1:=(-B+SQRT(D))/(2*A);
X2:=(-B+SQRT(D))/(2*A);
END;
END;
PROCEDURE XET(X:REAL);
BEGIN
IF X>0 THEN BEGIN
WRITELN('X=',SQRT(X));
WRITELN('X=',-SQRT(X));
END ELSE IF X=0 THEN WRITELN('X=0');
END;
BEGIN
WRITELN('NHAP LAN LUOT 3 SO A, B, C');
READLN(A,B,C);
GPT(A,B,C);
XET(X1);XET(X2);
IF (X1<0)AND(X2<0) THEN WRITELN('PHUONG TRINH VO NGHIEM');
READLN;
END.
