Algebra
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Algebra is all about finding what is missing  in a puzzle. For example, _ + 3 = 5. The answer here is 2. In algebra we use letters for the missing puzzle piece, usually an X or Y, but any letter is fine. The letter just means that we don't know what this number is, it is often called the variable or the unknown. So using the first example, you would say x  + 3 = 5. And the answer would be x = 2.The basic laws of algebra are the associative, cumulative and distributive laws. They help explain the relationships between numbers and help in simplifying equations to solve.
The general arithmetic operations performed in the case of algebra are:

Addition: x + y
Subtraction: x – y
Multiplication: x * y
Division: x / y or x ÷ y

Where x and y are the variables.The order of operations: The terms inside the brackets are considered first. Then, roots and exponents are operated on second priority. Solve all the division and multiplication operations and later addition and subtraction.Basic Formulas in AlgebraThe general formulas used in algebra to solve algebraic equations and find the values of unknown variables are given here:

a2 – b2 = (a – b)(a + b)
(a + b)2 = a2 + 2ab + b2
a2 + b2 = (a – b)2 + 2ab
(a – b)2 = a2 – 2ab + b2
(a + b + c)2 = a2 + b2 + c2 + 2ab + 2ac + 2bc
(a – b – c)2 = a2 + b2 + c2 – 2ab – 2ac + 2bc
(a + b)3 = a3 + 3a2b + 3ab2 + b3
(a – b)3 = a3 – 3a2b + 3ab2 – b3