Solve for x: x² + 8x - 9 = 0
Difficulty: Medium
About this MCQ
Medium SAT item. Correct choice: A. x = 1 or x = -9.
- A. x = 1 or x = -9 ✓
- B. x = 1 or x = -8
Why not B: “x = 1 or x = -8” is not x = 1 or x = -9.
- C. x = 2 or x = -10
Why not C: “x = 2 or x = -10” is not x = 1 or x = -9.
- D. x = -1 or x = 9
Why not D: “x = -1 or x = 9” is not x = 1 or x = -9.
Correct answer
A. x = 1 or x = -9
Explanation
x = 1 or x = -9 (option A) is the accepted answer to “Solve for x: x² + 8x - 9 = 0”. Option B (x = 1 or x = -8) is a different value from x = 1 or x = -9. Option C (x = 2 or x = -10) is a different value from x = 1 or x = -9. Option D (x = -1 or x = 9) is a different value from x = 1 or x = -9. Keep x = 1 or x = -9 as the SAT fact for this stem.
Source: Original practice question, MCQsHub
Tags: SAT, Math, Algebra, American Exams
Submitted by: MCQsHub Editorial
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