9*x (x - 1)*(7 - x) <= --- 4
(7 - x)*(x - 1) <= (9*x)/4
Or(And(4 <= x, x < oo), And(x <= 7/4, -oo < x))
((4 <= x)∧(x < oo))∨((x <= 7/4)∧(-oo < x))
(-oo, 7/4] U [4, oo)
x in Union(Interval(-oo, 7/4), Interval(4, oo))