program giaiptbac2;
uses crt;
var a, b, c, d, x, x1, x2: real;
begin
clrscr;
write('Nhap 3 so a, b, c'); readln(a,b,c);
if a = 0 then write('Phuong trinh khong thoa man dieu kien')
else
begin
d:=b*b-4*a*c;
if d < 0 then write ('Phuong trinh vo nghiem');
if d = 0 then
begin
x:=(-b)/(2*a);
write('Phuong trinh co nghiem kep x1=x2=',x:10:2);
end;
if d > 0 then
begin
x1:=(-b+sqrt(d))/(2*a);
x2:=(-b-sqrt(d))/(2*a);
write('Phuong trinh co 2 nghiem');
write('x1=',x1:10:2);
write('x2=',x2:10:2);
end;
end;
Readln
End.
