Official ExplanationTranslate the words into math symbols, noting that eight less than the square of \(x\) translates into x-squared minus 8, so \(x^2 – 8 < 8\). Add 8 to both sides, and \(x^2 < 16.\) Avoid carelessly taking the square-root of each side to obtain x < 4,
(B), because this approach neglects consideration of negative values. Negative numbers that are more than 4 units from 0 will become positive and greater than 16 when squared, failing to satisfy the inequality. All numbers less than 4 units from 0 in either direction will be less than 16 when squared: The values of x within the shaded region, \(–4 < x < 4, (D),\) satisfy the inequality.
Answer: DAttachment:
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