Algebraic Equations, examples

 

Algebraic Equations

Algebraic equations are two algebraic expressions that are joined together using an equal to ( = ) sign. An algebraic equation is also known as a polynomial equation because both sides of the equal sign contain polynomials. An algebraic equation is built up of variables, coefficients, constants as well as algebraic operations such as addition, subtraction, multiplication, division, exponentiation, etc.

If there is a number or a set of numbers that satisfy the algebraic equation then they are known as the roots or the solutions of that equation. In this article, we will learn more about algebraic equations, their types, examples, and how to solve algebraic equations.

What is Algebraic Equations?

An algebraic equation is a mathematical statement that contains two equated algebraic expressions. The general form of an algebraic equation is P = 0 or P = Q, where P and Q are polynomials. Algebraic equations that contain only one variable are known as univariate equations and those which contain more than one variable are known as multivariate equations. An algebraic equation will always be balanced. This means that the right-hand side of the equation will be equal to the left-hand side.

Algebraic Expressions

A polynomial expression that contains variables, coefficients, and constants joined together using operations such as addition, subtraction, multiplication, division, and non-negative exponentiation is known as an algebraic expression. An algebraic expression should not be confused with an algebraic equation. When two algebraic expressions are merged together using an "equal to" sign then they form an algebraic equation. Thus, 5x + 1 is an expression while 5x + 1 = 0 will be an equation.

Algebraic Equations Examples

x² - 5x = 3 is a univariate algebraic equation while y²x - 5z = 3x is an example of a multivariate algebraic equation.

Types of Algebraic Equations

Algebraic equations can be classified into different types based on the degree of the equation. The degree can be defined as the highest exponent of a variable in an algebraic equation. Suppose there is an equation given by x⁴ + y³ = 3⁵ then the degree will be 4. In determining the degree, the exponent of the constant or coefficient is not considered. The number of roots of an algebraic equation depends on its degree. An algebraic equation where the degree equals 5 will have a maximum of 5 roots. The various types of algebraic equations are as follows:

Linear Algebraic Equations

A linear algebraic equation is one in which the degree of the polynomial is 1. The general form of a linear equation is given as a1x1+a2x2+...+anxn = 0 where at least one coefficient is a non-zero number. These linear equations are used to represent and solve linear programming problems.

Example: 3x + 5 = 5 is a linear equation in one variable. y = 2x - 6 is a linear equation in two variables.

Quadratic Algebraic Equations

An equation where the degree of the polynomial is 2 is known as a quadratic algebraic equation. The general form of such an equation is ax² + bx + c = 0, where a is not equal to 0.

Example: 3x² + 2x - 6 = 0 is a quadratic algebraic equation. This type of equation will have a maximum of two solutions.

Cubic Algebraic Equations

An algebraic equation where the degree equals 3 will be classified as a cubic algebraic equation. ax³ + bx² + cx + d = 0 is the general form of a cubic algebraic equation (a ≠ 0).

Example: x³ + x² - x - 1 = 0. A cubic algebraic equation will have a maximum of three roots as the degree is 3.

Higher-Order Polynomial Algebraic Equations

Algebraic equations that have a degree greater than 3 are known as higher-order polynomial algebraic equations. Quartic (degree = 4), quintic (5), sextic (6), septic (7) equations all fall under the category of higher algebraic equations. Such equations might not be solvable using a finite number of operations.

Algebraic Equations Formulas

Algebraic equations can be simplified using several formulas and identities. These help to expedite the process of solving a given equation. Given below are some important algebraic formulas:

• (a + b)² = a² + 2ab + b²
• (a - b)² = a² - 2ab + b²
• (a + b)(a - b) = a² - b²
• (x + a)(x + b) = x² + x(a + b) + ab
• (a + b)³ = a³ + 3a²b + 3ab² + b³
• (a - b)³ = a³ - 3a²b + 3ab² - b³
• a³ + b³ = (a + b)(a² - ab + b²)
• a³ - b³ = (a - b)(a² + ab + b²)
• (a + b + c)² = a² + b² + c² + 2ab + 2bc + 2ca
• Quadratic Formula: [-b ± √(b² - 4ac)]/2a
• Discriminant: b² - 4ac

How to Solve Algebraic Equations

There are many different methods that are available for solving algebraic equations depending upon the degree. If an algebraic equation has two variables then two equations will be required to find the solution. Thus, it can be said that the number of equations required to solve an algebraic equation will be equal to the number of variables present in the equation.