Solve This Linear Equation: D = ?

by Andrew McMorgan 34 views

Hey math whizzes and number crunchers! Today, we're diving deep into the fascinating world of linear equations. You know, those algebraic puzzles that can seem a bit daunting at first glance, but are actually super satisfying to crack. We've got a specific one for you today: d−10−2d+7=8+d−10−3dd-10-2 d+7=8+d-10-3 d. Your mission, should you choose to accept it, is to find the value of 'd' that makes this equation true. We've laid out some options for you: A. d=−5d=-5, B. d=−1d=-1, C. d=1d=1, and D. d=5d=5. Which one is the golden ticket? Let's break it down step-by-step, shall we? Get ready to flex those brain muscles, because by the end of this, you'll not only know the answer but also feel a whole lot more confident tackling similar problems.

Simplifying Both Sides of the Equation

The very first thing we need to do, guys, is to simplify each side of the equation independently. Think of it like tidying up your room before you can actually figure out where everything belongs. On the left side, we have d−10−2d+7d-10-2 d+7. Let's group our 'd' terms together and our constant terms together. So, we have (d−2d)(d - 2d) and (−10+7)(-10 + 7). Combining these gives us −d−3-d - 3. Pretty neat, right? Now, let's move over to the right side of the equation: 8+d−10−3d8+d-10-3 d. Again, we group the 'd' terms: (d−3d)(d - 3d) and the constant terms: (8−10)(8 - 10). This simplifies to −2d−2-2d - 2. So, after this initial tidying-up phase, our equation now looks much cleaner: −d−3=−2d−2-d - 3 = -2d - 2. See? It's already starting to look less scary. This simplification step is crucial because it removes any potential confusion from having too many terms cluttering up the equation. By combining like terms, we make the structure of the equation much clearer, allowing us to isolate the variable more effectively in the subsequent steps. Remember, the goal here is to reduce complexity. Don't rush this part; make sure you've correctly identified and combined all the 'd' terms and all the constant terms on each side. Mistakes made here will carry through the entire problem, so a little extra attention now saves a lot of headaches later. This process highlights a fundamental principle in algebra: simplification is key. Whether you're dealing with simple linear equations or more complex polynomial or trigonometric equations, the ability to simplify expressions by combining like terms is an indispensable skill. It's the foundation upon which more advanced algebraic manipulations are built. So, take a moment to appreciate the elegance of simplification – it's your best friend in the world of math problems!

Isolating the Variable 'd'

Alright, we've successfully simplified both sides, and our equation is now −d−3=−2d−2-d - 3 = -2d - 2. The next big move is to get all the 'd' terms on one side of the equation and all the constant numbers on the other. This is the core of solving for 'd'. Let's start by moving the '-2d' term from the right side to the left side. How do we do that? By doing the opposite operation! Since it's currently being subtracted, we'll add '2d' to both sides of the equation. This gives us: (−d−3)+2d=(−2d−2)+2d(-d - 3) + 2d = (-2d - 2) + 2d. Simplifying this, we get d−3=−2d - 3 = -2. Now, we need to get that constant term, '-3', away from the 'd'. We do the opposite again: add '3' to both sides. So, we have (d−3)+3=−2+3(d - 3) + 3 = -2 + 3. And voilà! We are left with d=1d = 1. Boom! We've isolated 'd'. The process of isolating a variable involves a strategic dance of inverse operations. Each step must be applied equally to both sides of the equation to maintain balance. If you add something to one side, you must add it to the other. If you subtract from one side, you must subtract from the other. The same applies to multiplication and division. This principle of balance is fundamental to algebra and is often visualized as a scale: whatever you do to one side, you must do to the other to keep it level. In our case, we first added 2d2d to both sides to gather all the variable terms on the left. This neutralized the −2d-2d on the right side. Then, we added 33 to both sides to isolate the dd term, moving the constant terms to the right. This neutralization of the −3-3 on the left side left us with the variable dd standing alone. The elegance of this method lies in its systematic nature. By applying inverse operations, we systematically peel away the numbers and operations surrounding the variable until it stands by itself, revealing its value. This methodical approach ensures accuracy and builds confidence, transforming a potentially confusing problem into a clear, solvable one. It's a testament to the power of logical progression in mathematics, where each step logically follows the previous one, leading us inevitably to the correct solution. It's like following a treasure map, where each clue leads you closer to the final prize – the value of 'd'.

Verifying the Solution

We've found that d=1d=1. But are we sure? In the world of mathematics, especially when dealing with equations, verification is key! It's always a good practice to plug our answer back into the original equation to make sure it holds true. Our original equation was d−10−2d+7=8+d−10−3dd-10-2 d+7=8+d-10-3 d. Let's substitute d=1d=1 into this. On the left side: (1)−10−2(1)+7=1−10−2+7(1) - 10 - 2(1) + 7 = 1 - 10 - 2 + 7. Combining these numbers: 1−10=−91 - 10 = -9, then −9−2=−11-9 - 2 = -11, and finally −11+7=−4-11 + 7 = -4. So, the left side equals −4-4. Now, let's check the right side: 8+(1)−10−3(1)=8+1−10−38 + (1) - 10 - 3(1) = 8 + 1 - 10 - 3. Combining these: 8+1=98 + 1 = 9, then 9−10=−19 - 10 = -1, and finally −1−3=−4-1 - 3 = -4. Both the left side and the right side equal −4-4! Since −4=−4-4 = -4, our solution d=1d=1 is correct. This step of verification is super important, guys. It's your safety net. It catches any small errors you might have made during the solving process. If, for instance, we had gotten different values for the left and right sides, we would know to go back and recheck our steps. This thoroughness ensures that the answer we present is not just a guess but a mathematically sound result. It reinforces the concept that equations represent a balance, and our solution must satisfy that balance perfectly. Think of it as a final quality check before shipping out your work. This rigorous approach builds not only accuracy but also trust in your mathematical abilities. When you consistently verify your solutions, you develop a deeper understanding of how equations function and a greater confidence in your problem-solving skills. It transforms math from a series of abstract rules into a practical tool for confirming truth and certainty. So, never skip the verification step; it's your proof of correctness and your pathway to true mathematical mastery. It solidifies the learning and ensures that the understanding gained is robust and reliable.

Conclusion: The Correct Answer

So, after simplifying both sides of the equation d−10−2d+7=8+d−10−3dd-10-2 d+7=8+d-10-3 d, combining like terms, and strategically isolating the variable 'd', we arrived at the value d=1d=1. We then performed a crucial verification step, plugging d=1d=1 back into the original equation, which confirmed that both sides indeed equal −4-4. This confirms that our solution is accurate. Therefore, out of the options provided (A. d=−5d=-5, B. d=−1d=-1, C. d=1d=1, D. d=5d=5), the correct answer is C. d=1d=1. Solving linear equations might seem like a small piece of the vast mathematical puzzle, but mastering these fundamentals is what builds a strong foundation for tackling more complex challenges down the road. Keep practicing, keep questioning, and most importantly, keep having fun with numbers! Remember, every equation you solve is a small victory, a step towards becoming a math ninja. The journey of learning is continuous, and each problem you conquer adds another tool to your arsenal, making you more capable and confident. Embrace the process, learn from any mistakes, and celebrate your successes. The world of mathematics is full of fascinating patterns and logical structures waiting to be discovered, and your ability to navigate it grows with every equation you solve. So, go forth and conquer more math challenges!