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Advanced MathEasy–MediumCounting distinct solutions of a perfect square

Advanced Math practice question

How many distinct real solutions does x² − 10x + 25 = 0 have?

  1. A. Exactly oneCorrect
  2. B. Exactly two
  3. C. None
  4. D. Infinitely many

Answer: A. Exactly one

The left side is (x − 5)², which is zero only at x = 5 — one distinct solution.

Why the other answers are wrong

B. Exactly two
Both factors are the same (x − 5), so the two roots coincide.
C. None
x = 5 does satisfy the equation.
D. Infinitely many
A nonzero quadratic cannot vanish everywhere.

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