Advanced Math practice question

Answer: A. 4x² − 12x + 9

(2x − 3)² means (2x − 3)(2x − 3). Multiply out: 2x·2x − 2x·3 − 3·2x + 3·3 = 4x² − 6x − 6x + 9 = 4x² − 12x + 9.

Why the other answers are wrong

B. 4x² + 9

The two middle products, −6x and −6x, were skipped. Squaring a binomial always produces a middle term — here −12x.

C. 4x² − 9

This is the difference-of-squares pattern, (2x − 3)(2x + 3). But both factors here are (2x − 3), so the middle terms don't cancel and the constant is +9.

D. 2x² − 12x + 9

The coefficient 2 must be squared along with the x: (2x)² = 4x², not 2x².

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