Entry Exam Category: High School Equivalency Exams
Course: HiSET
Exam: HiSET Math Practice Test
Practice Question
Which of the following equations does not represent y as a function of x in the standard (x, y) coordinate plane?
Answer Choices
- A: y = x
- B: y = x + 2
- C: y = x² + 2
- D: x = y + 2
- E: x = y² + 2
Correct Answer: E
Rationale: A function has one y per x. A, B, C define y explicitly as a function of x. D: x = y + 2 → y = x - 2, a function. E: x = y² + 2 → y² = x - 2, y = ±√(x - 2), not a function (two y values). Options: A, B, C, D incorrect; E correct.