Year 9 Interactive Maths - Second Edition

The Lowest Common Multiple (LCM) of Expressions

You will recall that the LCM of 4 and 6 is 12.  This is found as follows:

Method for Finding the LCM

• Factorise each expression
• Find the product of each factor with the highest power which occurs in the given expressions.
  
  This product represents the LCM of the expressions.

Example 10

Find the LCM of x – 8 and 8 – x.

Solution:

Example 11

Solution:

Example 12

Solution:

Example 13

Solution:

Key Terms

lowest common multiple, LCM