Advanced MathVery hardNumber of solutions of a quadratic equation
Advanced Math practice question
How many distinct real solutions does the equation 4x² − 12x + 9 = 0 have?
- A. Exactly oneCorrect
- B. Exactly two
- C. None
- D. Infinitely many
Answer: A. Exactly one
The discriminant is 144 − 144 = 0, so one repeated root: (2x − 3)² = 0, x = 3/2.
Why the other answers are wrong
- B. Exactly two
- Two distinct roots need a positive discriminant.
- C. None
- None would need a negative discriminant.
- D. Infinitely many
- A quadratic has at most two solutions.
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