Question

Factor the expression. Tell which special product factoring pattern you used. $$169-x^{2}$$

Short answer

The factored form of the expression \(169 - x^{2}\) is therefore \((13 - x)(13 + x)\). The factoring pattern used here is the difference of squares.

Step-by-step solution

Identify the Squares

First, identify two perfect squares in the given expression. Here, the term \(169\) can be written as \(13^{2}\) (since \(13\) times \(13\) gives \(169\)), and \(x^{2}\) is the square of \(x\)

Apply Difference of Squares Formula

Apply the difference of squares formula, i.e., \(a^{2} - b^{2} = (a + b)(a - b)\). Substituting \(a=13\) and \(b=x\) into the formula, the expression \(169 - x^{2}\) becomes \((13 - x)(13 + x)\)

Key concepts

Special Product Factoring Patterns

Understanding special product factoring patterns is essential for simplifying complex algebraic expressions. These patterns reflect specific ways that algebraic expressions can be rewritten using multiplication or factoring. One of the most commonly used special product patterns is the difference of squares.

This pattern arises when an expression is in the form of one square subtracted from another, such as \( a^2 - b^2 \). The beauty of this pattern lies in its simplicity for factoring: it can always be broken down into the product of \( a - b \) and \( a + b \). Knowledge of this pattern allows students to swiftly deconstruct even seemingly difficult expressions into more manageable factors.

Applying this knowledge to our exercise \(169 - x^2\), we recognize the pattern of two squared terms. We can then factor it efficiently as the product of two binomials. By identifying these special factoring patterns, students can enhance their problem-solving skills and simplify complex algebraic tasks with ease.

Perfect Squares

Perfect squares play a critical role in algebra, especially when it comes to factoring expressions like the difference of squares. A perfect square is a number that is the product of an integer with itself. For instance, the number \(25\) is a perfect square because it equals \(5^2\), or \(5 \times 5\).

In the context of our exercise, \(169\) is identified as a perfect square because it is the square of \(13\), which is \(13^2\). Similarly, \(x^2\) is another perfect square, being the square of \(x\). Recognizing these perfect squares is a crucial step in applying the difference of squares formula correctly, as it forms the basis for understanding how to deconstruct the expression into its factors.

Difference of Squares Formula

The difference of squares formula is a powerful tool that allows for the simplification of expressions containing the subtraction of two perfect squares. Expressed mathematically as \(a^2 - b^2 = (a + b)(a - b)\), it's a principle that can dramatically reduce the complexity of certain algebraic expressions.

To harness this formula properly, one must identify the perfect squares in the expression, as seen in the exercise with \(169\) and \(x^2\). Once identified, the easy substitution of \(a\) and \(b\) with the square roots of the perfect squares—that is, \(13\) and \(x\) in our case—transforms the expression into a product of binomials. In the given exercise, \(169 - x^2\) is elegantly factored into \(13 - x\) and \(13 + x\) by recognizing and applying the difference of squares formula. This methodical approach to factoring provides a reliable shortcut to simplifying algebraic expressions involving perfect squares.