Solve X² - 5x - 14 = 0: Find The Value Of X

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Introduction

Hey guys! Today, let's dive into the fascinating world of quadratic equations. Specifically, we're going to tackle the equation x² - 5x - 14 = 0. Don't worry if it looks intimidating at first; we'll break it down step by step. Solving quadratic equations is a fundamental skill in algebra, with applications ranging from physics to engineering and even economics. Understanding how to find the values of x that satisfy this equation will not only boost your math skills but also give you a powerful tool for problem-solving in various fields. So, grab your thinking caps, and let's get started on this mathematical adventure together! We'll explore different methods to solve this equation, ensuring you grasp each concept thoroughly. By the end of this article, you'll be a quadratic equation-solving pro!

Understanding Quadratic Equations

Before we jump into solving our specific equation, let's take a moment to understand what quadratic equations are and why they're so important. At its core, a quadratic equation is a polynomial equation of the second degree. This means that the highest power of the variable (in our case, x) is 2. The general form of a quadratic equation is ax² + bx + c = 0, where a, b, and c are constants, and a is not equal to 0. If a were 0, the equation would become a linear equation, which is a different beast altogether. The coefficients a, b, and c play crucial roles in determining the nature and number of solutions (also known as roots) of the equation. These roots are the values of x that make the equation true. Quadratic equations pop up everywhere in real-world applications. For example, they can describe the trajectory of a projectile (like a ball thrown in the air), the shape of a suspension bridge cable, or the optimal dimensions for a rectangular garden to maximize area. They're also essential in more advanced mathematical concepts, such as calculus and complex analysis. The beauty of quadratic equations lies in their versatility and the numerous methods we have to solve them. Whether it's factoring, completing the square, or using the quadratic formula, each technique offers a unique approach to finding the elusive values of x. So, let's keep this in mind as we move forward and delve deeper into the methods for solving our equation x² - 5x - 14 = 0.

Methods to Solve Quadratic Equations

Alright, let's talk about the toolbox we have at our disposal for solving quadratic equations. There are primarily three main methods we can use, each with its own strengths and when to apply them. These methods are factoring, completing the square, and the quadratic formula. Understanding each method will give you a well-rounded approach to tackling any quadratic equation that comes your way. First up is factoring, which is often the quickest method when it works. Factoring involves breaking down the quadratic expression into two binomial factors. If we can find these factors, we can easily set each factor equal to zero and solve for x. However, not all quadratic equations can be factored easily, especially if the roots are not integers or simple fractions. The second method is completing the square. This technique involves manipulating the equation to create a perfect square trinomial on one side. While it might seem a bit more involved than factoring, completing the square is a powerful method because it works for any quadratic equation. It's also the method used to derive the quadratic formula, so understanding it gives you a deeper appreciation for the formula itself. Last but not least, we have the quadratic formula. This is the Swiss Army knife of quadratic equation solving—it works every single time, regardless of the nature of the roots. The quadratic formula is given by x = (-b ± √(b² - 4ac)) / 2a, where a, b, and c are the coefficients from the quadratic equation in the form ax² + bx + c = 0. While it might look intimidating, the quadratic formula is straightforward to use once you get the hang of plugging in the values. Each of these methods has its place, and choosing the right one can save you time and effort. For our equation x² - 5x - 14 = 0, we'll explore which method works best and why. So, let's dive into applying these techniques!

Solving x² - 5x - 14 = 0 by Factoring

Now, let's roll up our sleeves and get to work on solving our specific quadratic equation: x² - 5x - 14 = 0. We'll start with the factoring method, as it's often the quickest and most elegant solution when it applies. The goal of factoring is to rewrite the quadratic expression as a product of two binomials. In other words, we want to find two expressions of the form (x + p)(x + q) such that when multiplied together, they give us x² - 5x - 14. To do this, we need to find two numbers, p and q, that satisfy two conditions: their product must be equal to the constant term (-14), and their sum must be equal to the coefficient of the x term (-5). Let's think about the factors of -14. We have pairs like 1 and -14, -1 and 14, 2 and -7, and -2 and 7. Which of these pairs adds up to -5? Bingo! The pair 2 and -7 fits the bill perfectly because 2 + (-7) = -5 and 2 * (-7) = -14. So, we can rewrite our quadratic equation as (x + 2)(x - 7) = 0. Now comes the fun part. To find the values of x that make this equation true, we use the zero-product property. This property states that if the product of two factors is zero, then at least one of the factors must be zero. So, we set each factor equal to zero: x + 2 = 0 and x - 7 = 0. Solving these two simple linear equations, we get x = -2 and x = 7. These are the two roots, or solutions, of our quadratic equation. We've successfully factored the equation and found the values of x that satisfy it. Isn't it satisfying when a plan comes together? Factoring can be a powerful tool, but let's remember it's not always the best approach for every quadratic equation. Next, we'll explore another method to ensure we have a solid grasp on all our options.

Using the Quadratic Formula to Solve x² - 5x - 14 = 0

Even though we've already solved our equation by factoring, let's tackle it using the quadratic formula as well. This is an excellent exercise to reinforce our understanding of the formula and see how it provides a consistent solution, regardless of whether the equation is easily factorable. Remember, the quadratic formula is x = (-b ± √(b² - 4ac)) / 2a, where a, b, and c are the coefficients from the standard form of a quadratic equation, ax² + bx + c = 0. In our equation, x² - 5x - 14 = 0, we can identify the coefficients as follows: a = 1 (the coefficient of x²), b = -5 (the coefficient of x), and c = -14 (the constant term). Now, let's plug these values into the quadratic formula. We get: x = (-(-5) ± √((-5)² - 4 * 1 * -14)) / (2 * 1). Let's simplify this step by step. First, we have -(-5), which becomes 5. Then, we calculate (-5)² as 25. Next, we multiply 4 * 1 * -14, which gives us -56. So, inside the square root, we have 25 - (-56), which simplifies to 25 + 56 = 81. Our equation now looks like this: x = (5 ± √81) / 2. The square root of 81 is 9, so we have x = (5 ± 9) / 2. Now, we have two possible solutions, one with the plus sign and one with the minus sign. Let's calculate them separately. For the plus sign, we have x = (5 + 9) / 2 = 14 / 2 = 7. For the minus sign, we have x = (5 - 9) / 2 = -4 / 2 = -2. Lo and behold, we've arrived at the same solutions we found by factoring: x = 7 and x = -2. This demonstrates the power and reliability of the quadratic formula. It might seem a bit more involved than factoring in this case, but it's a foolproof method that works for any quadratic equation. Understanding how to use the quadratic formula is an essential tool in your mathematical arsenal. So, give yourself a pat on the back for mastering this technique! We've now solved our equation using two different methods, reinforcing our understanding and problem-solving skills.

Verifying the Solutions

Okay, guys, we've found our solutions for the quadratic equation x² - 5x - 14 = 0, which are x = 7 and x = -2. But how can we be absolutely sure that these values are correct? That's where verification comes in! It's always a good practice to plug your solutions back into the original equation to check if they satisfy it. This not only confirms your answer but also helps you catch any potential errors you might have made along the way. Let's start by verifying x = 7. We'll substitute 7 for x in the original equation: (7)² - 5(7) - 14 = 0. Simplifying, we get 49 - 35 - 14 = 0. And indeed, 49 - 35 - 14 equals 0, so x = 7 is definitely a solution. Now, let's verify x = -2. We'll substitute -2 for x in the original equation: (-2)² - 5(-2) - 14 = 0. Simplifying, we get 4 + 10 - 14 = 0. And once again, 4 + 10 - 14 equals 0, so x = -2 is also a valid solution. By verifying our solutions, we've gained confidence that our answers are correct. This step is crucial in mathematics because it ensures accuracy and reinforces your understanding of the problem-solving process. Think of it as the final stamp of approval on your hard work. So, remember to always verify your solutions whenever possible. It's a simple yet powerful way to ensure your success in math. We've now not only solved the equation but also confirmed our solutions, making us true quadratic equation-solving champions!

Conclusion

Alright, guys, we've reached the end of our journey through the quadratic equation x² - 5x - 14 = 0. We've explored what quadratic equations are, learned about different methods to solve them, and successfully found the values of x that satisfy our equation. We started by understanding the basics of quadratic equations and their importance in various fields. Then, we delved into the different methods for solving them: factoring and the quadratic formula. We applied the factoring method, breaking down the equation into (x + 2)(x - 7) = 0 and finding the solutions x = -2 and x = 7. We then reinforced our understanding by using the quadratic formula, which confirmed the same solutions. Finally, we verified our solutions by plugging them back into the original equation, ensuring our answers were correct. Solving quadratic equations is a valuable skill that opens doors to more advanced mathematical concepts and real-world applications. By mastering techniques like factoring and the quadratic formula, you've added powerful tools to your problem-solving arsenal. Remember, practice makes perfect, so keep tackling those quadratic equations! The more you practice, the more comfortable and confident you'll become. Math can be challenging, but it's also incredibly rewarding. Each problem you solve is a step forward in your understanding of the world around you. So, keep exploring, keep learning, and never stop questioning. You've got this! We hope this article has been helpful and has made the process of solving quadratic equations a little less daunting and a lot more fun. Keep up the great work, and we'll see you next time for another mathematical adventure!