By Baptist Johnson | Updated August 30, 2022
Algebra, a foundational branch of pure mathematics, focuses on the rules governing expressions and equations. In algebraic equations, letters—called variables—represent unknown numbers. To determine a variable’s value, we isolate it on one side of the equation using fundamental operations such as addition, subtraction, multiplication, and division.
Carefully examine the equation and locate the variable. It can be any letter from a to z.
Decide which operations will move all other terms to the opposite side. For example, in x – 4 = 10, the subtraction sign signals that we’ll use addition and subtraction. In 2x – 4 = 10, the coefficient 2 indicates that we’ll also need multiplication and division.
Follow the order of operations (Parentheses, Exponents, Multiplication & Division, Addition & Subtraction). This ensures each step is carried out correctly.
Use the chosen operations on both sides of the equation to solve for the variable. For instance, in x – 4 = 10, add 4 to each side: x = 14. In 2x – 4 = 10, divide by 2 to get x – 2 = 5, then add 2 to find x = 7.
Substitute the found value back into the original equation to confirm its validity.
The key is to apply the necessary operations on both sides of the equation until the variable stands alone.
For more practice, visit Khan Academy Algebra 1 or Math is Fun.
