The use of the letter x as a mathematical unknown is a relatively modern convention. Algebra has been around for a lot longer. Daryl Benson/Stockbyte via Getty Images You might be most familiar with x ...

The letter “x” often symbolizes something unknown, with an air of mystery that can be appealing. Illustration by Meilan Solly Even though “x” is one of the least-used letters in the English alphabet, ...

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Top students can benefit greatly by being offered the subject early. But many districts offer few Black and Latino eighth graders a chance to study it. By Troy Closson From suburbs in the Northeast to ...

Peter Schumer does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond ...