Solving Inequalities: A Comprehensive Guide
Hey guys! Today, we're diving into the world of inequalities, specifically tackling the problem: . Don't worry, it's not as scary as it looks! We'll break it down step-by-step, making sure you understand every move. Inequalities are mathematical statements that compare two expressions, showing that one is greater than, less than, greater than or equal to, or less than or equal to the other. They're super important in all sorts of real-world applications, from figuring out how much you need to earn to stay within a budget, to understanding how much of a certain ingredient you need in a recipe. Understanding how to solve inequalities is a fundamental skill in algebra, so let's get started. We'll analyze this equation and then look at how to solve it.
Simplifying the Inequality
Our first goal is to simplify the inequality. To do this, we'll combine like terms. Looking at the right side of the inequality (), we see that we have two terms with 'x' in them, and two constant terms. Let's deal with the 'x' terms first. We have and . Combining these gives us . Cool, right? Now let's tackle the constants. We have and . Adding these gives us . So, we can rewrite the right side of the inequality as . Our inequality now looks like this: . We've simplified it quite a bit, making it easier to work with. Remember, simplifying is all about making the equation easier to solve by combining similar values.
So, let's recap that first step: We started with . We then combined the 'x' terms, which were and , resulting in . Next, we added the constant terms, which were and , resulting in . By simplifying, we rewrote the right side of the equation as . The whole expression is now .
Isolating the Variable 'x'
Now that we've simplified our inequality, the next step is to isolate the variable 'x'. This means we want to get 'x' all by itself on one side of the inequality. To do this, we need to get rid of the that's currently with the 'x'. How do we do that? We perform the inverse operation. Since we're adding , we'll subtract from both sides of the inequality. Remember, whatever you do to one side of an inequality, you must do to the other side to keep it balanced. So, we subtract from both sides of the inequality: . On the left side, . On the right side, cancels out, leaving us with just 'x'.
Therefore, we are left with . This can also be written as . This is our solution! It tells us that 'x' must be greater than . Any number greater than will satisfy the original inequality. Think about it: if you plug in a number like into the original inequality, it holds true. If you plug in a number less than , like , it doesn't. This is a very crucial step in solving the expression. Isolating the variable is like finding the hidden treasure (x) at the end of a treasure hunt! You need to remove everything else that is not part of the treasure. The main thing is to be accurate with your math; missing a step might have severe consequences.
Determining the Correct Answer
Now that we've solved the inequality and found that , we can look at the multiple-choice options and find the correct one. We're looking for the option that says 'x is greater than 28'. Let's go through the options:
- A) - This matches our solution perfectly! This is the correct answer.
- B) - This says 'x is less than 28'. This is the opposite of our solution, so it's incorrect.
- C) - This says 'x is greater than 4'. While this is true, it's not the complete and accurate solution. We know is greater than , not just .
- D) - This says 'x is less than 4'. This is the complete opposite of our solution and is incorrect.
So, the correct answer is A) . Congratulations, you've solved the inequality! Always remember to double-check your work, especially when dealing with inequalities. Make sure the direction of the inequality sign is correct, and that you've performed the inverse operations correctly.
Visualizing the Solution
While we've found the answer algebraically, it's also helpful to visualize the solution on a number line. Imagine a number line that extends infinitely in both directions. We know that . On our number line, we would mark the point . Since is greater than , we would use an open circle at (because itself is not included in the solution), and shade everything to the right of . This shaded area represents all the values of that satisfy the inequality.
This visual representation can help you understand the solution more intuitively. It gives you a picture of all the possible values of 'x' that make the inequality true. For example, you could see that 29 would satisfy the equation. However, you can also see that a lower value, say would be out of the shaded area, making it not a correct answer. Visualizing the solution helps reinforce your understanding and can be very helpful, especially when you're first learning about inequalities. It's a great way to build your intuition and check your work. It makes it easier to see how the solution relates to all possible values.
Real-World Application Examples
Inequalities aren't just abstract math problems; they're incredibly useful in real-world scenarios. Let's imagine a couple of examples:
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Budgeting: You're saving up for a new video game console that costs $300. You've already saved $50, and you plan to save $10 per week. The inequality representing this scenario would be , where 'w' is the number of weeks. Solving this inequality would tell you how many weeks you need to save to afford the console. You would isolate 'w' to find out how many weeks you need to save to afford it.
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Earning Money: You need to earn at least $500 this month to pay your bills. You earn $10 per hour at your part-time job. The inequality would be , where 'h' is the number of hours you need to work. Solving this would tell you the minimum number of hours you need to work. If you earned less than $500, you could not pay the bills, and that is not a good situation.
As you can see, inequalities are powerful tools for problem-solving in everyday life. They help you set goals, make plans, and stay within limits. They're extremely relevant to personal finance, business decisions, and various scientific applications. Understanding inequalities is a really practical and important skill.
Tips for Solving Inequalities
Here are a few tips to help you master solving inequalities:
- Combine like terms: Always start by simplifying both sides of the inequality by combining like terms. This will make the equation easier to handle. This includes constants as well as variables.
- Isolate the variable: Your goal is to get the variable by itself on one side of the inequality. Use inverse operations to achieve this.
- Remember the sign flip: When you multiply or divide both sides of an inequality by a negative number, you must flip the direction of the inequality sign. This is a crucial rule to remember! Many people miss this point, and this can lead to many problems.
- Check your work: Always plug your solution back into the original inequality to make sure it holds true. This is a great way to catch any mistakes. This will help ensure the accuracy of your work.
- Practice, practice, practice: The more you practice, the better you'll become at solving inequalities. Work through different examples, and don't be afraid to ask for help if you get stuck. Do as many exercises as you can.
Inequalities are fundamental to success in more complex mathematical areas. They are the building blocks of many more complicated equations. With practice, you'll become confident in solving them!