Mastering Rational Equations: Solve $\frac{1}{h-5}+\frac{2}{h+5}=\frac{16}{h^2-25}$

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Mastering Rational Equations: Solve $\frac{1}{h-5}+\frac{2}{h+5}=\frac{16}{h^2-25}$

Hey there, math enthusiasts and problem solvers! Are you ready to dive deep into the fascinating world of rational equations? Today, we're going to tackle a super common type of problem that often pops up in algebra classes and standardized tests: solving for the unknown variable, h, in an equation like 1h−5+2h+5=16h2−25\frac{1}{h-5}+\frac{2}{h+5}=\frac{16}{h^2-25}. This isn't just about crunching numbers; it's about understanding the underlying principles of algebraic manipulation, factoring, finding common denominators, and most importantly, recognizing and avoiding those sneaky extraneous solutions. We're going to break it down step-by-step, making sure you grasp every single concept, and by the end of this guide, you'll be a pro at solving these kinds of problems with confidence. So grab your thinking caps, guys, because we're about to unlock the secrets to mastering rational equations and ensuring you never get tripped up by them again!

Unpacking the Mystery: What Exactly Are We Solving?

Alright, let's kick things off by really understanding what we're looking at with our equation: 1h−5+2h+5=16h2−25\frac{1}{h-5}+\frac{2}{h+5}=\frac{16}{h^2-25}. This, my friends, is a classic rational equation, which simply means it involves fractions where the numerator and/or denominator contain polynomials. Our main goal here is to find the value(s) of h that make this entire statement true. Think of it like a puzzle where h is the missing piece, and we need to use all our algebraic tools to reveal its identity. Before we even touch a single number, there's a critical first step that many people often overlook, but it's absolutely essential for solving these problems correctly: identifying the domain restrictions. What does that mean? Well, in mathematics, you can never divide by zero. Ever! So, we need to figure out what values of h would make any of our denominators equal to zero, because those values are forbidden.

Looking at our denominators, we have (h−5)(h-5), (h+5)(h+5), and (h2−25)(h^2-25). If h−5=0h-5 = 0, then h=5h = 5. If h+5=0h+5 = 0, then h=−5h = -5. And notice that h2−25h^2-25 is a difference of squares that factors into (h−5)(h+5)(h-5)(h+5), so its restrictions are the same: h≠5h \neq 5 and h≠−5h \neq -5. These are our domain restrictions or excluded values. Write them down, put them in neon lights, tattoo them on your brain – seriously, these are super important because any solution we find for h that happens to be 5 or -5 will be an extraneous solution and must be discarded. Ignoring this step is how many students mistakenly pick incorrect answers, so let's promise each other we won't make that mistake, okay? Now that we've got our boundaries set, we can confidently move on to the actual solving process, knowing exactly which values for h are off-limits.

Step-by-Step Breakdown: Conquering the Denominators

Factoring and Common Denominators: Your Key to Unlocking Rational Equations

When we're dealing with rational equations, especially those involving multiple fractions with different denominators, the first big hurdle is often getting rid of those pesky denominators. The absolute best way to do this, guys, is by finding the Least Common Denominator (LCD) of all the fractions involved. But before we can even think about the LCD, we need to ensure all our denominators are in their fully factored form. This is a crucial step that many students skip, leading to more complicated algebra later on, so let's not make that mistake! In our equation, 1h−5+2h+5=16h2−25\frac{1}{h-5}+\frac{2}{h+5}=\frac{16}{h^2-25}, we have three denominators: (h−5)(h-5), (h+5)(h+5), and (h2−25)(h^2-25). The first two, (h−5)(h-5) and (h+5)(h+5), are already as simple as they can get; they're prime polynomials. However, that third denominator, h2−25h^2-25, screams for attention! This expression is a classic example of a difference of squares. Remember that awesome algebraic identity: a2−b2=(a−b)(a+b)a^2 - b^2 = (a-b)(a+b)? Well, here, h2h^2 is our a2a^2 and 2525 is our b2b^2 (since 52=255^2=25). So, we can factor h2−25h^2-25 into (h−5)(h+5)(h-5)(h+5).

Now that we've factored h2−25h^2-25 into (h−5)(h+5)(h-5)(h+5), let's list all our denominators in their factored glory: (h−5)(h-5), (h+5)(h+5), and (h−5)(h+5)(h-5)(h+5). To find the LCD, we need to include every unique factor present in any of the denominators, raised to the highest power it appears in any single denominator. In this case, our unique factors are (h−5)(h-5) and (h+5)(h+5), and each appears only once in any given term's denominator. Therefore, the Least Common Denominator (LCD) for our entire equation is simply (h−5)(h+5)(h-5)(h+5). Understanding and correctly identifying the LCD is paramount because it's the magical tool that will allow us to transform our fraction-filled equation into a much simpler, no-fraction polynomial equation. This step truly sets the stage for a smooth sailing solution process, ensuring we combine terms effectively and avoid unnecessary complexity. Without this foundational understanding of factoring and LCDs, solving rational equations becomes a much more daunting task, but with it, we're already halfway to victory!

Clearing the Fractions: The Power Move to Simplify Your Equation

Alright, guys, now that we've successfully identified our Least Common Denominator (LCD) as (h−5)(h+5)(h-5)(h+5), it's time for the real game-changer: clearing the fractions. This is where the magic happens, transforming our scary-looking rational equation into a much more approachable linear (or sometimes quadratic) equation without any denominators! The strategy is straightforward: we're going to multiply every single term on both sides of our equation by the LCD. Think of it like hitting a