program equation;

var x, y: real;

begin
writeln('Enter the value of x: ');
readln(x);

if x >= 8 then
begin
y := -sqr(x) + x - 9;
end
else
begin
y := 1 / (power(x, 4) - 6);
end;

writeln('The value of y is: ', y);
end.