SOLUTION: The price of a large pepperoni pizza is $13.45 at New England Pizza, $13.50 at Romeo’s, and $15 at Front Row. These shops charge $6.25, $10.50, and $8, respectively, for a Greek

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Question 1163777: The price of a large pepperoni pizza is $13.45 at New England Pizza, $13.50 at Romeo’s, and $15 at Front Row. These shops charge $6.25, $10.50, and $8, respectively, for a Greek salad. What would each shop charge for two pizzas and a dozen salads? Show how this problem can be solved by forming two suitable matrices and then multiplying them.
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
you would use the dot product to multiply a 3 row 2 column matrix by a 2 row 1 column matrix.

your result matrix will be a 3 row 1 column matrix.

your two matrices are:


first matrix.

13.45      6.25
13.50      10.5
15         8

second matrix.

2
12

result matrix.

101.9
153
126



the procedure will be as follows:

row 1 column 1 of the result matrix is equal to 2 * 13.45 + 12 * 6.25 = 101.9
row 2 column 1 of the result matrix is equal to 2 * 13.50 + 12 * 10.5 = 153
row 3 column 1 of the result matrix is equal to 2 * 15 + 12 * 8 = 126

here's a matrix multiplication calculator that confirms the results are good.

https://matrix.reshish.com/multiplication.php

here are the results.







here's a reference.

https://www.intmath.com/matrices-determinants/matrix-multiplication-examples.php