Finding The Width Of A Rectangle Given Its Area And Length

by Admin 59 views

Hey guys! Ever found yourself staring at a math problem that seems like a tangled mess? Well, today, we're going to untangle one of those together. We've got a rectangle, and we know its area and length, but the width is playing hide-and-seek. No worries, we're turning into math detectives and cracking this case wide open!

The Challenge: Area, Length, and the Missing Width

Let's break down the problem. We're told that the area of our rectangle is given by the expression (x⁴ + 4x³ + 3x² - 4x - 4), which might look intimidating at first glance, but trust me, we've got this. The length of the rectangle is (x³ + 5x² + 8x + 4). Now, the key piece of information here is the good old formula we all know and love: Area = Length × Width. Our mission, should we choose to accept it (and we do!), is to find the width. Remember the relationship between area, length, and width is very important here. Understanding this relationship will guide us toward the correct solution. The area is the product of the length and the width. Therefore, to find the width, we need to do the opposite of multiplication, which is division. This means we will be dividing the area by the length to find the width. Polynomial division can be a bit tricky, but with careful steps and attention to detail, we can solve it successfully. So, let's dive into the process of polynomial long division.

Diving into Polynomial Long Division

So, how do we find the width when we know the area and the length? We use division! Since Area = Length × Width, it means Width = Area / Length. This is where polynomial long division comes into play. Think of it like regular long division with numbers, but now we're dealing with expressions with 'x's. The process might seem a little daunting at first, but breaking it down step by step makes it totally manageable. First, we set up the division problem, placing the area polynomial (x⁴ + 4x³ + 3x² - 4x - 4) inside the division symbol and the length polynomial (x³ + 5x² + 8x + 4) outside. Now, we focus on the leading terms of both polynomials. We ask ourselves, what do we need to multiply the leading term of the length (x³) by to get the leading term of the area (x⁴)? The answer is x. This x becomes the first term of our quotient, which will represent the width. Next, we multiply the entire length polynomial by this x, which gives us x(x³ + 5x² + 8x + 4) = x⁴ + 5x³ + 8x² + 4x. We then subtract this result from the area polynomial. This step is crucial because it helps us eliminate the leading term and simplify the problem. The subtraction yields:

(x⁴ + 4x³ + 3x² - 4x - 4) - (x⁴ + 5x³ + 8x² + 4x) = -x³ - 5x² - 8x - 4

Notice how the x⁴ terms cancel out, which is exactly what we wanted. Now we bring down the next term from the area polynomial, but since we've already included all the terms, we just work with the new polynomial we have: -x³ - 5x² - 8x - 4. We repeat the process. What do we need to multiply by to get -x³? The answer is -1. This becomes the next term in our quotient. We multiply the length polynomial by -1, getting -1(x³ + 5x² + 8x + 4) = -x³ - 5x² - 8x - 4. Subtracting this from our current polynomial gives:

(-x³ - 5x² - 8x - 4) - (-x³ - 5x² - 8x - 4) = 0

We get a remainder of 0, which means the division is exact, and we've found our width!

Decoding the Polynomial Division Process

The polynomial long division might seem complex, but it's a systematic approach to dividing polynomials. It's like solving a puzzle, where each step brings us closer to the solution. To recap, the first crucial step is setting up the problem correctly. We place the polynomial we are dividing (the dividend, which is the area in our case) inside the division symbol and the polynomial we are dividing by (the divisor, which is the length) outside. Next, we focus on the leading terms. We determine what term we need to multiply the leading term of the divisor by to obtain the leading term of the dividend. This term becomes part of our quotient. We then multiply the entire divisor by this term and subtract the result from the dividend. This process eliminates the leading term of the dividend, simplifying the problem. We bring down the next term (if any) and repeat the process until we either have no more terms to bring down or the degree of the remainder is less than the degree of the divisor. The quotient we obtain is the result of the division, which in our case, is the width of the rectangle. The remainder, if any, represents what's left over after the division. In our specific problem, we had a remainder of 0, which means the division was clean and the length divides evenly into the area. The key to mastering polynomial long division is practice. The more problems you solve, the more comfortable you'll become with the process. It's also essential to be meticulous with your calculations, especially when dealing with negative signs and exponents. A small error in one step can throw off the entire solution. So, take your time, double-check your work, and remember that each step is logical and builds upon the previous one.

Unveiling the Width: Our Solution

After performing the polynomial long division, we found that the quotient is (x - 1). And guess what? That's the width of our rectangle! Woohoo! High fives all around! So, the correct answer is D. x - 1. We successfully navigated the polynomial division and uncovered the hidden width. Remember, the key to these problems is breaking them down into manageable steps and understanding the underlying concepts. Now, let's celebrate our victory by recapping the journey we took to get here. We started with the problem statement, where we were given the area and length of a rectangle in polynomial form and asked to find the width. We recognized the fundamental relationship between area, length, and width: Area = Length × Width. This relationship led us to the realization that we needed to divide the area by the length to find the width. We then embarked on the adventure of polynomial long division, a process that might have seemed intimidating at first but became clear as we broke it down step by step. We carefully set up the division problem, focusing on the leading terms and systematically eliminating them through subtraction. We continued this process until we reached a remainder of 0, indicating a clean division. The quotient we obtained, (x - 1), was the width of the rectangle, the solution we were seeking. This problem highlights the power of algebraic manipulation and the importance of understanding fundamental formulas. It also demonstrates that even seemingly complex problems can be solved by breaking them down into smaller, more manageable steps. So, the next time you encounter a challenging math problem, remember our adventure with the rectangle and the missing width. Take a deep breath, break the problem down, and apply the tools you've learned. You might be surprised at what you can achieve!

Final Thoughts: Math is an Adventure!

Math problems like this might seem like puzzles at first, but they're actually adventures waiting to be explored. By understanding the rules (like the area formula) and using the right tools (like polynomial long division), we can conquer any challenge. So, keep practicing, keep exploring, and most importantly, keep having fun with math!