Formulas are mathematical expressions that show the relationship between different variables. They are used in various fields, such as mathematics, science, and engineering, to calculate values or describe patterns. A common example is the area of a rectangle, which is calculated using the formula: Area = length × width. In addition to mathematics, formulas are essential in chemistry for representing chemical reactions, like the formula for water, H₂O. They help simplify complex information, making it easier to understand and apply in real-world situations. Formulas can be simple or complex, depending on the concepts they represent.