\( \frac{\text { Question } 3}{\text { Factorise completely } x a-x b+3 a-3 b} \)

To factorise the expression \(x a - x b + 3 a - 3 b\) completely, we can group the terms: \[ x(a - b) + 3(a - b) \] Now, we can factor out the common term \((a - b)\): \[ (a - b)(x + 3) \] And there you have it! The expression is completely factorised as \((a - b)(x + 3)\). Another way to look at it involves understanding that factoring is essentially rewriting the expression in terms of its roots or components. This can simplify solving equations and allows you to see connections between different functions more clearly. Factoring often helps in identifying zeroes of the function, which can be particularly useful in graphing or solving polynomial equations.