Simplifying Square Roots: A Step-by-Step Guide

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Hey everyone, let's dive into the world of simplifying square roots! Today, we're going to tackle an expression that looks a bit intimidating at first glance: 125+28βˆ’85\sqrt{125} + \sqrt{28} - 8\sqrt{5}. Don't worry; we'll break it down into easy-to-understand steps. Simplifying square roots is a fundamental skill in algebra, and once you get the hang of it, it's like a superpower! This guide will provide you with the ability to solve this problem easily and with confidence. We'll go through the process methodically, explaining each step so you can follow along and understand the 'why' behind each move. By the end of this, you'll be simplifying square roots like a pro, ready to conquer any problem thrown your way. So, grab a pen and paper, and let's get started on this mathematical adventure!

Understanding the Basics of Square Roots

Before we jump into the simplification, let's quickly recap what square roots are all about, yeah? Square roots are the inverse operation of squaring a number. When we say x\sqrt{x}, we're asking, "What number, when multiplied by itself, equals x?" For example, 9=3\sqrt{9} = 3 because 3 * 3 = 9. Now, not all numbers have nice, whole-number square roots. That's where simplifying comes in. The goal of simplifying square roots is to rewrite the expression so that any perfect squares (like 4, 9, 16, 25, etc.) are taken out from under the radical sign, leaving the simplest form of the expression. It's like cleaning up a room - we want to take out the clutter (perfect squares) and leave behind only the essential items. One of the key concepts here is the product rule for square roots: aβˆ—b=aβˆ—b\sqrt{a * b} = \sqrt{a} * \sqrt{b}. This rule allows us to break down a large number under a square root into the product of smaller numbers, making it easier to simplify. Remember, a perfect square is a number that results from multiplying an integer by itself. They're our golden ticket to simplifying square roots, so it's good to know them! Using these basics is critical to understanding the solution to this problem, and will help you to solve more advanced problems.

Identifying Perfect Squares and Prime Factors

To simplify square roots effectively, we need to be able to spot perfect squares and understand prime factorization. Let's get into detail on these two concepts. A perfect square is the result of squaring an integer. Knowing your perfect squares (1, 4, 9, 16, 25, 36, 49, 64, 81, 100, and so on) helps us quickly identify factors we can 'take out' of the square root. For instance, if we see 20\sqrt{20}, we immediately think, "Ah, 20 is 4 * 5, and 4 is a perfect square!" We can then rewrite 20\sqrt{20} as 4βˆ—5\sqrt{4} * \sqrt{5}, which simplifies to 252\sqrt{5}. Prime factorization, on the other hand, is the process of breaking down a number into a product of prime numbers. A prime number is a whole number greater than 1 that has only two divisors: 1 and itself (e.g., 2, 3, 5, 7, 11, etc.). Understanding prime factorization helps us to find the perfect square factors more systematically, especially with larger numbers. For example, let's take 125. We can factorize 125 as 5 * 5 * 5, or 535^3. In this case, we can rewrite 125\sqrt{125} as 25βˆ—5\sqrt{25 * 5}, which simplifies to 555\sqrt{5}. Combining these two concepts is the key to simplifying square root expressions. Practice recognizing perfect squares and finding prime factors, and you'll become much more adept at simplifying these kinds of problems!

Step-by-Step Simplification of 125+28βˆ’85\sqrt{125} + \sqrt{28} - 8\sqrt{5}

Alright, guys, let's get down to business and simplify the expression 125+28βˆ’85\sqrt{125} + \sqrt{28} - 8\sqrt{5}. We'll go step by step, making sure we don't miss anything. The key is to break down each square root into its simplest form, then combine like terms if possible. Follow along closely, and you'll see how it all falls into place. This process involves applying the product rule of square roots and looking for perfect square factors. Remember, we aim to rewrite the expression so that any perfect squares are removed from under the radical sign. Let’s do this! Each term in the expression has to be addressed individually, ensuring we simplify them one at a time. Once we've simplified each part, we'll see if any terms can be combined. The goal is to get all the square roots to have the same number under the radical if we want to combine them. Let's start simplifying this expression now. This step-by-step guide is designed to make this seemingly complex problem very easy to understand.

Simplifying 125\sqrt{125}

Let's begin with the first term, 125\sqrt{125}. As we mentioned earlier, we can factorize 125 into its prime factors: 5 * 5 * 5, or 535^3. Alternatively, we can see that 125 = 25 * 5. Since 25 is a perfect square, we can rewrite 125\sqrt{125} as 25βˆ—5\sqrt{25 * 5}. Then, applying the product rule, this becomes 25βˆ—5\sqrt{25} * \sqrt{5}. Since the square root of 25 is 5, the simplified form of 125\sqrt{125} is 555\sqrt{5}. We've now simplified our first term, pulling out the perfect square and leaving the remaining factor under the radical. This means that 125\sqrt{125} has been rewritten in its simplest form, and we can move on to the next part of the expression. Keep this result in mind, as we'll use it in the final step when we combine like terms. Remember, the most important thing is to identify perfect square factors.

Simplifying 28\sqrt{28}

Now, let's move on to the second term, 28\sqrt{28}. We need to find the perfect square factor of 28. We can factorize 28 as 2 * 2 * 7 or 4 * 7. Since 4 is a perfect square, we can rewrite 28\sqrt{28} as 4βˆ—7\sqrt{4 * 7}. Using the product rule, this becomes 4βˆ—7\sqrt{4} * \sqrt{7}. The square root of 4 is 2, so the simplified form of 28\sqrt{28} is 272\sqrt{7}. This is another key step in simplifying the overall expression. Notice how we're systematically reducing each square root. Identifying perfect square factors here is very important. This also shows how factoring skills are important for simplifying complex problems. Now we have two terms simplified, and we're one step closer to the final answer. Remember to keep the intermediate results, as they will be used at the end.

Simplifying 858\sqrt{5}

For the last term, 858\sqrt{5}, there isn't much to simplify because 5 has no perfect square factors (other than 1). The number 5 is a prime number, so it cannot be simplified further under the square root. So, we just leave this term as it is. 858\sqrt{5} is already in its simplest form. This step highlights that not all square roots can be simplified; sometimes, they are already in their most basic form. That's okay! Now we have successfully broken down each term individually and made sure that they are in the simplest possible form. Now the only step left is to combine them.

Combining the Simplified Terms

Alright, we've simplified each term in the original expression: 125+28βˆ’85\sqrt{125} + \sqrt{28} - 8\sqrt{5}. Now, let's put it all together. We found that 125=55\sqrt{125} = 5\sqrt{5}, 28=27\sqrt{28} = 2\sqrt{7}, and 858\sqrt{5} remains as is. Therefore, our expression becomes 55+27βˆ’855\sqrt{5} + 2\sqrt{7} - 8\sqrt{5}. We can now combine like terms. In this case, the like terms are the ones with 5\sqrt{5}. Adding 555\sqrt{5} and subtracting 858\sqrt{5} gives us βˆ’35-3\sqrt{5}. The term 272\sqrt{7} cannot be combined with anything, so we simply keep it. Our final simplified expression is βˆ’35+27-3\sqrt{5} + 2\sqrt{7}. This is the simplest form of the original expression. The process is completed, and this is the final solution. This combination step is what truly simplifies the expression. This final result cannot be simplified any further, as the terms have different radicals, and they cannot be combined. The final answer is expressed by the sum of a combination of numbers with different square roots.

Final Answer

So, guys, the simplified form of 125+28βˆ’85\sqrt{125} + \sqrt{28} - 8\sqrt{5} is βˆ’35+27-3\sqrt{5} + 2\sqrt{7}. We've successfully broken down each square root, identified perfect square factors, and combined like terms to reach the final, simplified expression. Great job everyone! Remember, the key takeaways here are understanding the product rule for square roots, recognizing perfect squares, and systematically simplifying each term. Practice is key, and the more you practice, the more comfortable you'll become with simplifying square roots. Keep up the excellent work, and you'll be tackling complex math problems with ease in no time. This knowledge will be useful when solving more complicated math problems in the future!