Solve: x2+5≥9x^2 + 5 \geq 9x2+5≥9.
x≥2x \geq 2x≥2
x≤−2x \leq -2x≤−2
x≥2x \geq 2x≥2 or x≤−2x \leq -2x≤−2
−2≤x≤2-2 \leq x \leq 2−2≤x≤2