| 1) | 4x -2y = 4 ; 4x + y = 5 | 2) | 2x + y = -1 ; 5x + 4y = 1 |
| 3) | 4x -3y = 1 ; 4 x -2 y = 4 | 4) | 4x -2y = 4 ; 4 x -2 y = 5 |
| 5) | 2x - y = 2 ; 4 x -4 y = 1 | 6) | 2x + 2y = 0 ; 5x + 3y = 9 |
| 7) | 3x -2y = 0 ; 5x + y = 7 | 8) | 4x - y = 4 ; 3 x -2 y = 8 |
| 9) | 3x - y = 6 ; 2 x -4 y = 1 | 10) | 3x -3y = 3 ; 3x - y = 1 |
| 11) | 2x + 3y = -3 ; 3x + 2y = 3 | 12) | 2x + 5y = 0 ; 3 x -3 y = 9 |
| 13) | 3x -3y = 3 ; 2x + 5y = 7 | 14) | 2x -3y = 6 ; 4x + y = 8 |
| 15) | 4x -4y = -1 ; 4x + 4y = 8 | 16) | 3x -2y = -1 ; 5x + 4y = 2 |
| 17) | 3x + 6y = 5 ; 3x - y = 10 | 18) | 4x -3y = 2 ; 6 x -4 y = 2 |
| 19) | 3x - y = -1 ; 2 x -2 y = 10 | 20) | 4x + 6y = -2 ; 2 x -2 y = 5 |
| 21) | 2x + 3y = 1 ; 5x + 3y = 6 | 22) | 4x + y = 1 ; 2 x -3 y = 8 |
| 23) | 3x - y = 5 ; 4x + y = 3 | 24) | 3x + 6y = 0 ; 3x + 5y = 10 |
| 25) | 2x -4y = -1 ; 6x + 3y = 4 | 26) | 2x + 3y = 2 ; 6x + 2y = 10 |
| 27) | 4x + 2y = 5 ; 5 x -3 y = 10 | 28) | 3x + 5y = 2 ; 2 x -5 y = 5 |
| 29) | 2x + 3y = 0 ; 6x + y = 9 | 30) | 2x -2y = 3 ; 5x + 5y = 6 |
| 31) | 4x + y = -3 ; 4x + 5y = 5 | 32) | 3x + y = 6 ; 6 x -4 y = 2 |
| 33) | 3x + 3y = -2 ; 6x + 5y = 9 | 34) | 2x + 3y = -2 ; 3x + 3y = 3 |
| 35) | 3x -4y = 1 ; 4 x -4 y = 4 | 36) | 2x + 5y = 4 ; 6 x -4 y = 3 |
| 37) | 2x -3y = 1 ; 2x + 2y = 9 | 38) | 3x + 4y = 4 ; 6x + 2y = 5 |
| 39) | 2x -3y = 6 ; 6x + 4y = 9 | 40) | 2x -3y = 5 ; 5 x -3 y = 2 |
Joke:
To err is human, to remember them in order, statistics; to plot them Excel!