Answer:
B
Explanation:
The dimensions of A and B are, respectively, (3, 2) and (2, 2). This means the dimensions of the product will be (3, 2), the same as A. This eliminates answer choices A and C immediately.
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To determine whether the answer is B or D, find a term in which those matrices differ. Then compute that term from A and B.
Here, term (1, 2) is -37 in choice B and -32 in choice D. The actual product term is the dot product of row 1 of A and column 2 of B:
[1, -4]ยท[7, 11] = (1)(7) +(-4)(11) = 7 -44 = -37 . . . . matches choice B
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Your scientific or graphing calculator can probably compute the matrix product for you. Certainly, any spreadsheet can, as shown in the attachment.