An algebraic sentence which has '=' sign is called an equation. An equation which has highest power is equal to one is known as linear equation for example, x + 4 = 0. The linear equation represent a straight line on the graph.

A function is an equation which indicates the relationship between two variables. A function represents the dependence of one variable on the other independent variable. For example equation of a straight line, equation of a parabola.

A function is an equation which indicates the relationship between two variables. A function represents the dependence of one variable on the other independent variable. For example equation of a straight line, equation of a parabola.