# Algebra

Algebra is a branch of mathematics in which arithmetic is extended to deal with unknown numbers or relationships, using letters or other symbols. These letters or symbols are called variables.

Example

Tyler counted the empty spaces in his stamp book. He found that he needs to collect only 37 more stamps to fill his book, which holds 500 stamps. How many stamps does he have already?

To solve this problem using algebra, first write an equation that describes the problem situation. Let s represent the number of stamps that Tyler already has.

s + 37 = 500

One way to solve for s is to subtract 37 from each side of the equation.

s + 37 - 37 = 500 - 37

s = 463

Thus, Tyler has 463 stamps.

See also variables.