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  • Appropriate dimensions


Students know:

  • The aspects of a matrix with regard to entries, rows, columns, dimensions, elements, and subscript notations.


Students are able to:

  • Strategically choose and apply appropriate representations of matrices on which arithmetic operations can be performed.


Students understand that:

  • Matrix addition and subtraction may be performed only if the matrices have the same dimensions.
  • Matrix multiplication can be performed only when the number of columns in the first matrix equal the number of rows in the second matrix.
  • There are many contextual situations where arithmetic operations on matrices allow us to solve problems.


  1. Add, subtract, and multiply matrices of appropriate dimensions.