Algebra

Algebra (from Arabic: الجبر, transliterated "al-jabr", meaning "completion") is a part of mathematics. It uses variables to represent a value that is not yet known or can be replaced with any value. When an equals sign (=) is used, this is called an equation. A very simple equation using a variable is: ${\displaystyle 2+3=x}$. In this example, ${\displaystyle x=5}$, or it could also be said that "${\displaystyle x}$ equals five". This is called solving for ${\displaystyle x}$.^[1]

Besides equations, there are inequalities (less than and greater than). A special type of equation is called the function. This is often used in making graphs because it always turns one input into one output.

Algebra can be used to solve real problems because the rules of algebra work in real life and numbers can be used to represent the values of real things. Physics, engineering and computer programming are areas that use algebra all the time. It is also useful to know in surveying, construction and business, especially accounting.

People who do algebra use the rules of numbers and mathematical operations used on numbers. The simplest are adding, subtracting, multiplying, and dividing. More advanced operations involve exponents, starting with squares and square roots.

Algebra was first used to solve equations and inequalities. Two examples are linear equations (the equation of a straight line, ${\displaystyle y=mx+b}$ or ${\displaystyle y=mx+c}$) and quadratic equations, which has variables that are squared (multiplied by itself, for example: ${\displaystyle 2\cdot 2}$, ${\displaystyle 3\cdot 3}$, or ${\displaystyle x\cdot x}$).

1. ↑ "Algebra Introduction". Math is Fun. Retrieved 11 April 2013.