# Exercises. Addition and subtraction of matrices

You can add and subtract matrices of same size, as result you get a matrix of the same size.

**Addition of matrices** (**sum of matrices**) **A** + **B** is the operation of finding the matrix **C**, all of whose elements are equal to the sum of pairwise all relevant elements of the matrices **A** and **B**, that is, each element of the matrix **C** is

_{i,j}= a

_{i,j}+ b

_{i,j}

**Subtraction of matrices** (**difference of matrices**) **A** - **B** is the operation of finding the matrix **C**, all of whose elements are pairwise differences of all relevant elements of the matrices **A** and **B**, that is, each element of the matrix **C** is

_{i,j}= a

_{i,j}- b

_{i,j}

Exercises. Addition of two matrices (sum of matrices) and the subtraction of two matrices (difference of matrices).

Given two matrices **A** and **B**:

A = | -9 |
-3 |
-11 |
||

-10 |
20 |
-7 |
|||

-15 |
20 |
4 |
|||

B = | 9 |
-11 |
-18 |
||

16 |
-20 |
6 |
|||

10 |
-10 |
-10 |
|||

Select the size of the matrix **С**:

Number of rows:

Number of columns:

C = | ... |

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