How to Find Rational Points Like Your Job Depends on It

You’re sitting at the end of a long conference table, interviewing for your dream job. You’ve made it this far, but there’s just one more question you have to answer. “Is it possible for a line that passes through the origin to pass through no other rational points?” Five pairs of intense eyes watch you, waiting for your response. Do you get the job? You might think this only happens in story…

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