Algebra is the branch of mathematics that uses variables, constants, and operations to represent and solve relationships between quantities. It forms the foundation for higher mathematics, from calculus to linear algebra, and is essential in science, engineering, economics, and data analysis. At its core, algebra teaches you to work with abstract symbols instead of specific numbers, allowing you to solve problems that would be tedious or impossible with arithmetic alone. The key mental model: an equation is a balance — whatever you do to one side, you must do to the other — and mastering this principle unlocks virtually every algebraic technique you'll encounter.

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