________ / 2 \/ 4 - x > 3*x
sqrt(4 - x^2) > 3*x
/ ____\ | \/ 10 | And|-2 <= x, x < ------| \ 5 /
(-2 <= x)∧(x < sqrt(10)/5)
____ \/ 10 [-2, ------) 5
x in Interval.Ropen(-2, sqrt(10)/5)