Simplifying Radical Expressions √20 + √75 - √125 A Step-by-Step Guide

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Introduction to Simplifying Radical Expressions

In the realm of mathematics, simplifying radical expressions is a fundamental skill that enhances our ability to work with numbers and equations. Radicals, often represented by the square root symbol (√), can sometimes appear complex, but they can be simplified to their most basic form. This process involves breaking down the number under the radical sign (the radicand) into its prime factors and then extracting any perfect squares. In this article, we will delve into the step-by-step process of simplifying the expression √20 + √75 - √125, providing a comprehensive understanding of the underlying principles and techniques involved.

The simplification of radical expressions is crucial for several reasons. First and foremost, it allows us to express numbers in their simplest form, making them easier to understand and compare. Complex radicals can obscure the true value of a number, while simplified radicals provide clarity. Secondly, simplifying radicals is often a necessary step in solving equations and performing algebraic manipulations. Many mathematical problems involve radicals, and simplifying them can make the problem more manageable. Finally, simplifying radicals enhances our overall mathematical fluency and problem-solving skills. It encourages us to think critically about numbers and their properties, fostering a deeper understanding of mathematical concepts. In the following sections, we will explore the specific steps involved in simplifying √20, √75, and √125, and then combine these simplified forms to arrive at the final answer. Through this detailed exploration, you will gain a solid foundation in simplifying radical expressions and be better equipped to tackle similar problems in the future.

Breaking Down √20: A Step-by-Step Guide

To begin simplifying the expression √20 + √75 - √125, our first task is to simplify each individual radical term. Let's start with √20. The key to simplifying radicals lies in identifying perfect square factors within the radicand. A perfect square is a number that can be obtained by squaring an integer (e.g., 4, 9, 16, 25, etc.). When we find a perfect square factor, we can extract its square root, thus simplifying the radical.

In the case of √20, we need to find the largest perfect square that divides 20. The factors of 20 are 1, 2, 4, 5, 10, and 20. Among these, 4 is a perfect square (since 2² = 4). Therefore, we can rewrite √20 as √(4 × 5). This is a crucial step because it allows us to separate the perfect square factor from the remaining factor.

Now, we can use the property of radicals that states √(a × b) = √a × √b. Applying this property, we get √(4 × 5) = √4 × √5. We know that √4 is equal to 2, so we can substitute this value into the expression. This gives us 2 × √5, which is commonly written as 2√5. This is the simplified form of √20. By extracting the perfect square factor, we have reduced the radical to its simplest terms, making it easier to work with in further calculations.

The process of breaking down √20 into its simplified form illustrates the fundamental principle of simplifying radicals: identifying and extracting perfect square factors. This technique is not only essential for simplifying individual radicals but also for combining them in expressions like √20 + √75 - √125. In the following sections, we will apply the same principle to simplify √75 and √125, building upon the skills we have developed here. Understanding this step-by-step approach is crucial for mastering the art of simplifying radical expressions and tackling more complex mathematical problems.

Simplifying √75: Unveiling the Perfect Square Factor

Having successfully simplified √20, we now turn our attention to the next term in the expression: √75. The process of simplifying √75 follows the same principle as before: identifying and extracting the largest perfect square factor from the radicand. This involves breaking down 75 into its factors and determining which of these factors is a perfect square.

The factors of 75 are 1, 3, 5, 15, 25, and 75. Among these factors, 25 is a perfect square because it is the result of squaring the integer 5 (5² = 25). Therefore, we can rewrite √75 as √(25 × 3). This separation of the perfect square factor is a critical step in the simplification process, as it allows us to apply the property of radicals that we used earlier.

Using the property √(a × b) = √a × √b, we can rewrite √(25 × 3) as √25 × √3. Since √25 is equal to 5, we can substitute this value into the expression, giving us 5 × √3, which is commonly written as 5√3. This is the simplified form of √75. By extracting the perfect square factor of 25, we have transformed the radical into its simplest equivalent form.

Simplifying √75 not only makes it easier to work with in calculations but also highlights the importance of recognizing perfect square factors. This skill is fundamental to simplifying radicals and is a key component of algebraic manipulations involving radicals. In the next section, we will apply this same technique to simplify √125, further solidifying our understanding of the process and preparing us to combine the simplified radicals in the original expression. The ability to efficiently simplify radicals is a valuable asset in mathematics, enabling us to tackle a wide range of problems with confidence and precision.

Deconstructing √125: Finding the Perfect Square

Having successfully simplified √20 and √75, we now move on to the final radical term in our expression: √125. The process of simplifying √125 is consistent with the methods we have used previously, focusing on identifying and extracting the largest perfect square factor from the radicand. This approach ensures that we reduce the radical to its simplest form, making it easier to work with in calculations.

To begin, we need to determine the factors of 125. The factors of 125 are 1, 5, 25, and 125. Among these factors, 25 stands out as a perfect square because it is the result of squaring the integer 5 (5² = 25). Therefore, we can rewrite √125 as √(25 × 5). This separation of the perfect square factor is a crucial step in the simplification process.

Now, we apply the property of radicals that states √(a × b) = √a × √b. Using this property, we can rewrite √(25 × 5) as √25 × √5. We know that √25 is equal to 5, so we substitute this value into the expression, giving us 5 × √5, which is commonly written as 5√5. This is the simplified form of √125. By extracting the perfect square factor of 25, we have successfully simplified the radical.

The simplification of √125 further reinforces the importance of recognizing perfect square factors when dealing with radicals. This skill is not only essential for simplifying individual radicals but also for combining them in more complex expressions. With √20, √75, and √125 now simplified, we are well-prepared to combine these simplified forms and arrive at the final answer for the expression √20 + √75 - √125. In the next section, we will perform this final step, demonstrating the power of simplifying radicals in solving mathematical problems.

Combining Simplified Radicals: The Final Calculation

With each individual radical term in the expression √20 + √75 - √125 now simplified, we are ready to combine them and arrive at the final answer. This process involves substituting the simplified forms of √20, √75, and √125 into the original expression and then performing the necessary arithmetic operations. The simplified forms we have obtained are 2√5 for √20, 5√3 for √75, and 5√5 for √125.

Substituting these values into the original expression, we get:

2√5 + 5√3 - 5√5

Now, we need to combine like terms. In this context, like terms are those that have the same radical part. We can see that 2√5 and -5√5 are like terms because they both have √5 as the radical part. However, 5√3 is not a like term because it has √3 as the radical part. Therefore, we can only combine 2√5 and -5√5.

Combining these like terms, we have:

(2√5 - 5√5) + 5√3

This simplifies to:

-3√5 + 5√3

Since -3√5 and 5√3 are not like terms, we cannot combine them further. Therefore, the final simplified form of the expression √20 + √75 - √125 is -3√5 + 5√3. This result demonstrates the power of simplifying radicals before performing arithmetic operations. By reducing each radical to its simplest form, we have made the expression easier to work with and arrived at a clear and concise answer.

In conclusion, the process of simplifying and combining radicals involves several key steps: identifying perfect square factors, extracting these factors from the radicand, simplifying individual radical terms, and then combining like terms. By mastering these techniques, we can confidently tackle a wide range of mathematical problems involving radicals. The final answer, -3√5 + 5√3, represents the simplified form of the original expression, showcasing the elegance and efficiency of simplifying radicals in mathematics.

Conclusion: Mastering Radical Simplification

In this comprehensive exploration, we have meticulously dissected the process of simplifying the expression √20 + √75 - √125. We began by understanding the fundamental concept of simplifying radicals, emphasizing the importance of identifying and extracting perfect square factors from the radicand. This foundational knowledge is crucial for effectively working with radical expressions and solving mathematical problems involving radicals.

We then embarked on a step-by-step journey, individually simplifying each radical term. For √20, we identified 4 as the perfect square factor, rewriting the radical as √(4 × 5) and simplifying it to 2√5. Similarly, for √75, we recognized 25 as the perfect square factor, rewriting the radical as √(25 × 3) and simplifying it to 5√3. Finally, for √125, we again identified 25 as the perfect square factor, rewriting the radical as √(25 × 5) and simplifying it to 5√5.

With each radical term simplified, we proceeded to the crucial step of combining like terms. We substituted the simplified forms into the original expression, resulting in 2√5 + 5√3 - 5√5. Recognizing that 2√5 and -5√5 were like terms, we combined them to obtain -3√5. Since -3√5 and 5√3 are not like terms, we could not simplify further, leading us to the final answer: -3√5 + 5√3.

This final result underscores the significance of simplifying radicals before performing arithmetic operations. By reducing each radical to its simplest form, we not only made the expression easier to work with but also arrived at a clear and concise answer. The process of simplifying and combining radicals involves a series of key steps, including identifying perfect square factors, extracting these factors from the radicand, simplifying individual radical terms, and combining like terms.

Mastering these techniques is essential for anyone seeking to excel in mathematics. The ability to simplify radicals is not only a fundamental skill but also a building block for more advanced mathematical concepts. By understanding the underlying principles and practicing the techniques, you can confidently tackle a wide range of mathematical problems involving radicals. The final simplified expression, -3√5 + 5√3, serves as a testament to the power and elegance of radical simplification in mathematics. This skill will undoubtedly prove invaluable as you continue your mathematical journey, enabling you to approach complex problems with clarity and precision.