Solve for x
x\in (-\infty,-4]\cup [4,\infty)
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x^{2}-16\geq 0
Multiply the inequality by -1 to make the coefficient of the highest power in -x^{2}+16 positive. Since -1 is negative, the inequality direction is changed.
x^{2}\geq 16
Add 16 to both sides.
x^{2}\geq 4^{2}
Calculate the square root of 16 and get 4. Rewrite 16 as 4^{2}.
|x|\geq 4
Inequality holds for |x|\geq 4.
x\leq -4\text{; }x\geq 4
Rewrite |x|\geq 4 as x\leq -4\text{; }x\geq 4.
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Limits
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