Answer :

Final answer:

Checkers was solved through alternative strategies and creative thinking.

Explanation:

Checkers was solved by exploring alternative strategies outside of the traditional approach, similar to solving puzzles or patterns, by thinking creatively and questioning initial assumptions. In the case of the checkers problem, individuals like Willem and Rachel found success by approaching the problem from a different perspective and considering unconventional solutions. This approach is very much like the strategies used by scientists such as the inventors of the quark hypothesis, who solved the puzzle of particle patterns by exploring all combinations and predicting previously unobserved elements. It's an illustration of using a heuristic approach, where general strategies based on past experiences, such as suspecting a trick, are applied to new problems.