**Quadratic equation, Pythagorean Theorem, simple interest equation, linear equations and cubic equations are some examples of common equations.** In mathematical terms, an equation states that two expressions are equal. It combines two expressions of equal value in a single condition with the left-hand side equaling the right-hand side.

Each expression in an equation is made of varying number of terms or variables. Variables in an equation are unknown and the process of solving the equation is to find the variable’s value. In mathematics, there are many types of equations. The type of an equation determines the method of their examination.

Polynomial equations, linear equations, parametric equations, Cartesian equations and differential equations are some of the many types of equations used in different branches of mathematics including algebra, arithmetic and geometry.

(y = mx + b) is a linear equation’s common form. (y = mx + b) is the slope-intercept equation of a line. [y – y1 = m(x - x1)] is the point slope equation of a line.

In geometry, geometric figures are properties are described using equations. Formulas for area, surface area, perimeter and volume of geometric figures are an example of this. Area of a rectangle is represented by (A = lw) where ‘w’ is width and ‘l’ is length.