13
QuizMultiple Choice

Solving Quadratic Equations — Test

Question 13 • Algebraic Reasoning

The square of 9 less than a number is 3 less than the number. What is the number?

Answer
A
negative 12 or 7
B
negative 12 or negative 7
C
negative 7 or 12
D
7 or 12

Explanation

Let the number be x. “9 less than a number” is x − 9, so the statement gives (x − 9)² = x − 3. Expanding and rearranging gives x² − 19x + 84 = 0, which factors as (x − 7)(x − 12) = 0. Thus the number is 7 or 12, choice B.

AI-written and checked against the verified answer.

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