A variable is a symbol that represents a quantity that can change or vary in value. It is usually represented by a letter, such as x or y. A constant, on the other hand, is a value that does not change and is represented by a number. In an equation, variables are often used to represent unknown values, while constants are known values.
To solve for a variable in an equation, you need to isolate the variable on one side of the equation. This can be done by using the inverse operation of the mathematical operation that is being performed on the variable. For example, if the equation is 2x + 5 = 15, you can solve for x by subtracting 5 from both sides and then dividing by 2. This will give you the value of the variable, which in this case is x = 5.
Parentheses are used in equations to indicate the order in which operations should be performed. This is known as the order of operations. Any operations within parentheses will be performed first, followed by exponents, multiplication and division (from left to right), and finally addition and subtraction (from left to right). This ensures that the equation is solved correctly and gives a clear understanding of the intended order of operations.
While you can technically use any letter as a variable in an equation, it is best to stick to using letters that are commonly used in mathematics, such as x, y, z, a, and b. This will make it easier for others to understand your equations and for you to follow along when solving them. It is also important to use a different letter for each variable in an equation to avoid confusion.
The equal sign in an equation represents balance or equivalence. It means that the value on one side of the equation is equal to the value on the other side. This is why it is important to perform the same operation on both sides of the equation in order to maintain the balance and find the correct solution.