Contents

Introduction

Solving Simple Equations

Formulae

Factorising Quadratic Equations

Completing the Square method

General Solution method

Problem Solving

Quiz 

Algebra Main Page

Solving Simple Equations

To solve an equations means to find the root or solution of the equation.

Example 1

Find the value of x in 5x + 6 = 13 - 9x

5x + 6 = 13 - 9x

5x + 6 + 9x = 13 (bring the x over to LHS)

14x + 6 = 13

14x = 7

x = 2

Example 2

Find the solution of 3(3 - 2x) - (1 + x) = 10 - 13x

3(3 - 2x) - (1 + x) = 10 - 13x

9 - 6x - 1 - x = 10 - 13x

8 - 7x = 10 - 13x

13x - 7x = 10 - 8

6x = 2

x = 1/3

Example 3

Solve 2x -(x + 5) = 2 -(7 - x)

2x -(x + 5) = 2 -(7 - x)

2x - x - 5 = 2 - 7 + x

x - 5 = -5 + x

x = x (identity)

Note: This is an identity. Equations with the same solution are known as identities.