A rectangular vegetable garden has a length of (x + 7) feet and a width of (x + 3) feet. Which polynomial represents the area of the garden in square feet?
Ax² + 21
Bx² + 10x + 21
C2x + 10
Dx² + 4x + 21
Explanation
Area = length × width = (x + 7)(x + 3). Use FOIL: x·x + x·3 + 7·x + 7·3 = x² + 3x + 7x + 21 = x² + 10x + 21. Choice A only multiplies the first and last terms (skips the middle). C is the perimeter formula 2(L + W) wrongly applied. D mixes up the middle coefficient.
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