7.1 Algebraic Formulae
7.1.1 Variables and Constant
1. A variable is a quantity without a fixed value.2. A constant is a quantity with a fixed value.
7.1.2 Concept of Formulae
1. An algebraic formula is an equation which shows the relationship between several variables and/ or constant.
2. The subject of an algebraic formula is a linear variable expressed in terms of the other variables.