Expand (2x + 3y)²:
A4x² + 12xy + 9y²
B4x² + 6xy + 9y²
C4x² − 12xy + 9y²
D2x² + 12xy + 3y²
Answer & Solution
Correct answer: A. 4x² + 12xy + 9y²
Using (a+b)² with a = 2x, b = 3y: a² = 4x², 2ab = 2·2x·3y = 12xy, b² = 9y². So (2x + 3y)² = 4x² + 12xy + 9y².
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