= -2/3 * 18/5 - 3/7 * 5/14

1. -2/3 * 18/5 = - 2 * 6/5

2. - 3/7 * 5/14 = - 3 * 2/5

3. - 2 * 6/5 = - 12/5

4. - 3 * 2/5 = - 6/5

5. - 12/5 - 6/5 = - 18/5 = - 3, 6