Question

Write the rational expression in simplest form.\(\frac{15 x^{2}}{10 x}\)

Short answer

The simplified form of the rational expression \(\frac{15 x^{2}}{10 x}\) is \(\frac{3*x}{2}\).

Step-by-step solution

Factor the Numerator and Denominator

Start by factoring the numerator and the denominator. In the numerator, \(15 x^{2}\) is the same as \(5*3*x*x\). In the denominator, \(10 x\) is the same as \(2*5*x\). This gives us a new expression: \(\frac{5*3*x*x}{2*5*x}\).

Cancel Common Factors

Now, look for the common factors in the numerator and denominator and cancel them. You can cancel out \(5\) and \(x\) which gives us the simplified expression: \(\frac{3*x}{2}\)

Write the Simplified Expression

Write the simplified expression which is \(\frac{3*x}{2}\). This means that \(\frac{15 x^{2}}{10 x}\) simplifies to \(\frac{3*x}{2}\).

Key concepts

Factoring Polynomials

Factoring polynomials is akin to breaking down a number into its prime factors, but with algebraic expressions. It is a crucial skill in simplifying rational expressions, as it allows us to see which terms can be reduced. For instance, when we look at the numerator of the rational expression \(15x^2\), we can divide it into prime factors and variables. It becomes \(5 \times 3 \times x \times x\). Similarly, the denominator \(10x\) factors into \(2 \times 5 \times x\).

Understanding the concept of factoring polynomials is fundamental and serves as the first step in simplifying. It is important to recognize common terms, such as numbers with shared prime factors and identical variables raised to a power, and arrange them appropriately. This preparation streamlines the process of canceling common factors, which further simplifies the expression.

Canceling Common Factors

After factoring polynomials, the next step is to cancel common factors present in both the numerator and the denominator. This step is crucial in simplifying rational expressions and requires careful attention to avoid mistakes. In our example, both the numerator and denominator share the factors \(5\) and \(x\).

By canceling them, we reduce the expression \(\frac{5 \times 3 \times x \times x}{2 \times 5 \times x}\) to \(\frac{3 \times x}{2}\). It's vital to remember that only like terms can be canceled—those that are identical in both the numerator and denominator. This is because dividing a number by itself yields one, effectively eliminating it from the expression. Canceling common factors simplifies the algebraic fraction, making it easier to work with and understand.

Algebraic Fractions

Algebraic fractions, much like their numerical counterparts, consist of a numerator and a denominator separated by a division symbol. They often contain variables and can be simplified through the processes of factoring and canceling, just as with numerical fractions. The simplified form of an algebraic fraction is more concise and more straightforward to use in further calculations.

For our example \(\frac{15x^2}{10x}\), the simplification process results in \(\frac{3x}{2}\) after factoring and canceling common factors. This final form is considered 'simplest' because no further reduction is possible. When students master the skill of simplifying algebraic fractions, they are better equipped to tackle complex algebraic equations and understand the relationships between algebraic quantities in mathematical expressions.