/ / _____\ / _____ \\
| | 15 \/ 129 | | 15 \/ 129 ||
Or|And|-4 <= x, x <= - -- + -------|, And|x <= -6, - -- - ------- <= x||
\ \ 2 2 / \ 2 2 //
$$\left(-4 \leq x \wedge x \leq - \frac{15}{2} + \frac{\sqrt{129}}{2}\right) \vee \left(x \leq -6 \wedge - \frac{15}{2} - \frac{\sqrt{129}}{2} \leq x\right)$$
((-4 <= x)∧(x <= -15/2 + sqrt(129)/2))∨((x <= -6)∧(-15/2 - sqrt(129)/2 <= x))
_____ _____
15 \/ 129 15 \/ 129
[- -- - -------, -6] U [-4, - -- + -------]
2 2 2 2
$$x\ in\ \left[- \frac{15}{2} - \frac{\sqrt{129}}{2}, -6\right] \cup \left[-4, - \frac{15}{2} + \frac{\sqrt{129}}{2}\right]$$
x in Union(Interval(-4, -15/2 + sqrt(129)/2), Interval(-15/2 - sqrt(129)/2, -6))