Question

Multiply the matrices. (Please help!)

Answer 1

9514 1404 393

Answer:

  $\left[\begin{array}{cc}12&1\\-4&1\\-11&28\end{array}\right]$

Step-by-step explanation:

The element at row i column j in the product is the dot-product of row i of the first matrix and column j of the second matrix. For example, row 2 column 1 of the product is ...

  (row 2) · (column 1)

  [3, -2, 4] · [2, 7, 1] = (3)(2) +(-2)(7) +(4)(1) = 6 -14 +4 = -4

The attachment shows the complete product matrix. It is convenient to let a spreadsheet or graphing calculator do the tedious repetitive arithmetic.