### Example 1

Express these equations using matrices.

3*x* + *y* = 0

-*x* – 5*y* = 4

### Example 2

Express these equations using matrices.

3*x* – 4*y* = -7

*x* + *y* = 9

### Example 3

Express these equations using matrices.

2*x* + 2*y* = 11

6*x* – *y* = 3

### Example 4

For the matrix below, identify: a) the rows, b) the columns, and c) each entry.

### Example 5

For the matrix below, identify: a) the rows, b) the columns, and c) each entry.

### Example 6

For the matrix below, identify: a) the rows, b) the columns, and c) each entry.

### Example 7

For the matrix below, identify: a) the rows, b) the columns, and c) each entry.

### Example 8

For the matrix below, identify: a) the rows, b) the columns, and c) each entry.