Simplify And Solve: 4x + 12 - 3x + 8 With X=5

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Simplify and Solve: 4x + 12 - 3x + 8 with x=5

Hey math whizzes! Ever stared at an expression and thought, "What in the world am I supposed to do with this?" Well, guys, today we're tackling just that. We've got a classic algebra puzzle: evaluate the expression 4x + 12 - 3x + 8 when x = 5. This might seem a bit daunting at first, but trust me, it's super straightforward once we break it down. We're going to dive deep into simplifying algebraic expressions and then plugging in our value for 'x' to find the final answer. So, grab your pencils, get comfy, and let's unravel this mathematical mystery together! We'll go step-by-step, making sure no one gets left behind. Understanding how to manipulate and solve these kinds of problems is a fundamental skill in mathematics, opening doors to more complex concepts later on. So, consider this your friendly introduction or a quick refresher. We'll cover what terms are, how to combine like terms, and the importance of order of operations (even though in this case, it's pretty simple!). By the end of this, you'll be a pro at evaluating expressions and maybe even impress your friends with your newfound math skills. Let's get this algebraic party started!

Understanding the Building Blocks: Terms and Variables

Alright, let's start with the basics, people! When we look at our expression, 4x + 12 - 3x + 8, we see a few different components. The most important ones to get a grip on are terms and variables. Think of terms as the individual pieces that make up the expression, separated by addition or subtraction signs. In our case, the terms are 4x, +12, -3x, and +8. See how they're all separate little units? Now, what about that 'x'? That, my friends, is our variable. A variable is basically a placeholder for a number that we don't know yet, or a number that can change. In this problem, we're specifically told to find the value of the expression when x = 5. This means we're going to substitute that number '5' in for every 'x' we see. The number sitting right next to the variable, like the '4' in 4x or the '3' in -3x, is called the coefficient. It tells us how many of that variable we have. So, 4x means we have four 'x's added together. It's like having four apples. -3x means we have negative three 'x's. The numbers without any variables attached, like 12 and 8, are called constants. They're constant because their value never changes. They're just plain old numbers. Getting comfortable with these terms – variable, coefficient, constant, and term – is super crucial because they are the language of algebra. Without understanding these, tackling more complex equations will feel like trying to read a book in a foreign language. We’ll also be dealing with positive and negative numbers, so make sure you’re solid on adding and subtracting those. Remember, the sign in front of a term belongs to that term. So, +12 is positive twelve, and -3x is negative three 'x'. This might seem like nitpicking, but in algebra, every little detail matters and can change the outcome of your calculation. So, let's give a nod to our terms: 4x, 12, -3x, and 8. And our star player, the variable x, which we know is 5 for this particular mission.

Simplifying Like a Pro: Combining Like Terms

Now that we know our terms, the next big step in making our expression 4x + 12 - 3x + 8 easier to handle is combining like terms. What does that even mean, you ask? It means we group together terms that are similar. Think of it like sorting your laundry – you put all the socks together, all the shirts together, etc. In algebra, 'like terms' are terms that have the exact same variable raised to the exact same power. In our expression, 4x and -3x are like terms because they both have the variable 'x' (and 'x' to the power of 1, which is usually just written as 'x'). The numbers 12 and 8 are also like terms because they are both constants (they have no variables). So, what we do is combine the coefficients of the like terms. For the 'x' terms, we have 4x and -3x. We combine these by performing the operation between their coefficients: 4 - 3. What does that give us? It gives us 1x, or simply x. Easy peasy! Now, let's look at our constants: +12 and +8. We combine these by adding them together: 12 + 8. And that gives us 20. So, when we combine our like terms in the original expression 4x + 12 - 3x + 8, we end up with a much simpler expression: x + 20. Isn't that neat? We've taken a slightly longer expression and boiled it down to its essence. This process of combining like terms is fundamental to solving equations and simplifying complex algebraic statements. It makes subsequent steps, like substitution, much less prone to errors. Imagine trying to plug x=5 into the original messy expression versus the clean x + 20. Big difference, right? This simplification step is where the real magic of algebra starts to show. It's about finding patterns and efficiencies. So, remember this rule: you can only combine terms that have the identical variable part. You can't combine 'x' terms with 'y' terms, or 'x²' terms with 'x' terms. Stick to what's alike, and you'll be golden. Now, our simplified expression is x + 20. We're almost there, guys! Just one more step to find our final numerical answer.

Plugging In the Value: Substitution in Action

We've done the heavy lifting! We've simplified our expression 4x + 12 - 3x + 8 down to x + 20. Now comes the exciting part: evaluating the expression, which means finding its numerical value. Remember that the problem asked us to evaluate this expression when x = 5? This is where we use that information. The process is called substitution. We're going to substitute, or replace, every 'x' in our simplified expression (x + 20) with the number 5. So, our expression x + 20 becomes (5) + 20. See what we did there? We took out the 'x' and put in the '5'. Using parentheses around the substituted value is a good habit, especially when dealing with negative numbers or more complex operations, as it helps prevent errors. Now, all that's left is to perform the simple arithmetic. We have 5 + 20. And what does that equal? Drumroll, please... 25! So, the value of the expression 4x + 12 - 3x + 8 when x = 5 is 25. Isn't that awesome? You just conquered an algebraic expression! This substitution step is a core concept in algebra and is used everywhere, from solving equations to understanding functions. It's how we can test out different scenarios or find specific answers based on given conditions. Think of it like a recipe: you have a set of instructions (the expression), and you have your ingredients (the value of x). When you combine them correctly, you get your final dish (the numerical answer). This process highlights the power of algebra – taking abstract symbols and turning them into concrete, understandable numbers. It's the bridge between the theoretical and the practical. Always remember to be careful with your substitution, especially if the number you're substituting is negative or if you're dealing with exponents. Double-checking your work at this stage can save you a lot of headaches later on. But for this particular problem, we nailed it! The final answer is 25.

The Final Answer and Why It Matters

So, to recap, we started with the expression 4x + 12 - 3x + 8 and were asked to find its value when x = 5. We first simplified the expression by combining like terms. We grouped the 'x' terms (4x and -3x) to get x, and we grouped the constant terms (12 and 8) to get 20. This left us with the much simpler expression x + 20. Then, we substituted the given value of x = 5 into our simplified expression. Replacing 'x' with '5' gave us 5 + 20, which equals 25. And there you have it – the final answer is 25! Why does this matter, you might ask? Well, mastering the skill of evaluating algebraic expressions is absolutely fundamental to your journey in mathematics. It's the gateway to understanding more complex concepts like solving equations, graphing functions, and even delving into calculus. When you can confidently simplify and substitute, you unlock the ability to model real-world situations. For instance, if 4x + 12 - 3x + 8 represented the cost of producing a certain number of items (x), then knowing the value is 25 when x=5 tells you the specific cost for producing 5 items. This ability to translate abstract mathematical forms into concrete values is what makes math so powerful and applicable. It's not just about numbers on a page; it's about understanding patterns, making predictions, and solving problems that affect our daily lives. So, pat yourselves on the back! You've not only solved a math problem but also reinforced a critical skill that will serve you well in future academic pursuits and beyond. Keep practicing, and you'll become even more adept at navigating the wonderful world of algebra. Remember, every problem you solve makes you stronger and more confident. Keep up the fantastic work, everyone!