Non-negative integers are positive integers or zero.
1. When then there are such possible cases for
and
In total 11 solutions for
2. For there are such possible cases for
and
In total 10 solutions for
3. This process gives you
- for
- 9 solutions;
- for
- 8 solutions;
- for
- 7 solutions;
- for
- 6 solutions;
- for
- 5 solutions;
- for
- 4 solutions;
- for
- 3 solutions;
- for
- 2 solutions;
- for
- 1 solution.
4. Add all numbers of solutions:
Answer: there are 66 possible solutions (with non-negative integer variables)