var a,b,c,d,x,x1,x2:real;
begin
write ('a='); read (a);
write ('b='); read (b);
write ('c='); read (c);
d:=b*b-4*a*c;
if d<0 then writeln ('NO')<br> else if d>0 then
begin
x1:=(-b+sqrt(d))/(2*a);
x2:=(-b-sqrt(d))/(2*a);
writeln ('x1=',x1:0:2,' x2=',x2:0:2)
end
else
begin
x:=-b/(2*a);
writeln ('x=',x);
end
end.