1. Adding & Subtracting Matrices
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2. In this Workshop you will:
Matrices
In this Workshop you will:
Learn the definition of a matrix.
Identify elements of a matrix.
Learn how to add matrices.
Learn how to subtract matrices.
Learn how to solve variable expressions using addition and subtraction of matrices.

3. Definition of a Matrix
A matrix is a rectangular or square array of elements arranged in rows and columns.
Numbers in a matrix are called its entries or elements.
NOTE: Entries may be numerical or variable expressions.

4. Elements of a Matrix amn= any element in row m and column n
m= number of rows
n= number of columns
amn= any element in row m and column n
m×n= dimension of a matrix

5. Addition
If two or more matrices have the same order (same number of rows and columns) matrices may be added to their corresponding entries.

6. Example 1: Find A + B
Solution:

7. Subtraction
Like in addition, matrices that have the same order may be subtracted from their corresponding entries.

8. Example 2: Find A - B
Solution:

9. Variables in Matrices Use A + B = C to solve for x, y, and z.
Solution:
Add elements in matrix A with elements in Matrix B
Rewrite elements in matrix A+B as variable expressions

10. Each Element in Matrix A+B corresponds to an element in matrix C
Each Element in Matrix A+B corresponds to an element in matrix C. Therefore, the solutions can be found by treating each element as a linear equation and solving for the indicated variable.
NOTE: Once x and y are found, there is no need to use A21 +B21 = C21 to solve.
A11+ B11 = C11
A12+ B12 = C12
A22+ B22 = C22

11. Matrices Links Adding and Subtracting Matrices Handout
Matrices Quiz
Multiplying and Dividing Matrices Workshop
Multiplying Matrices Handout
Gauss-Jordan Workshop
Gauss-Jordan Method Handout
Inverse Matrix Handout