var delta,a,b,c,x1,x2:real;
begin
write('Nhap a = ');Readln(a);
write('Nhap b = ');readln(b);
write('Nhap c = ');readln(c);
if a = 0 then write('Khong phai phuong trinh bac hai')
else
begin
delta:=b*b-4*a*c;
if delta = 0 then
begin
x1:=-b/(2*a);
write('Phuong trinh co nghiem kep x1 = x2 = ',x1:10:2);
end
end;
if delta>0 then
begin
writeln('Phuong trinh co hai nghiem phan biet ');
x1:=(-b+sqrt(delta))/(2*a);
x2:=(-b-sqrt(delta))/(2*a);
write('x1 = ',x1:10:2,' va x2 = ',x2:10:2);
end;
if delta < 0 then write('Phuong rinh vo nghiem');
readln;
end.
