Solving Inequalities A Step-by-Step Guide To $19 \geq 4-5n$

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In the realm of mathematics, inequalities play a crucial role in defining relationships between values that are not necessarily equal. Solving inequalities is a fundamental skill, extending the concepts of solving equations to scenarios where we seek a range of possible solutions rather than a single value. In this comprehensive guide, we will delve into the process of solving the inequality 19≥4−5n19 \geq 4 - 5n, providing a step-by-step approach that will not only help you understand the solution but also equip you with the knowledge to tackle similar problems. Our discussion will cover the core principles of inequality manipulation, the importance of maintaining the inequality's integrity throughout the solution process, and the interpretation of the final result. We will also explore the nuances of dealing with negative coefficients and how they affect the direction of the inequality. By the end of this guide, you will have a solid grasp of how to solve linear inequalities and be able to apply these techniques to a variety of mathematical contexts. Understanding inequalities is not just an academic exercise; it has practical applications in various fields, including economics, engineering, and computer science, where optimization and constraint satisfaction are essential. So, let's embark on this mathematical journey and unlock the secrets of solving inequalities. Remember, the key to mastering mathematics is not just memorizing steps but understanding the underlying principles. This guide aims to provide you with that understanding, ensuring that you can confidently approach any inequality problem that comes your way. Let's begin by dissecting the given inequality and identifying the steps required to isolate the variable and arrive at the solution. This process will involve a series of algebraic manipulations, each carefully designed to maintain the truth of the inequality while moving us closer to the answer. So, let's get started and unravel the mystery of 19≥4−5n19 \geq 4 - 5n.

Understanding Inequalities

Before we dive into the specifics of solving 19≥4−5n19 \geq 4 - 5n, let's establish a firm understanding of what inequalities are and how they differ from equations. Inequalities are mathematical statements that compare two expressions using symbols such as greater than (>>), less than (<<), greater than or equal to (≥\geq), and less than or equal to (≤\leq). Unlike equations, which seek a single value that makes the statement true, inequalities often have a range of values that satisfy the condition. This range is known as the solution set. The inequality 19≥4−5n19 \geq 4 - 5n states that the value of 19 is greater than or equal to the expression 4−5n4 - 5n. Our goal is to find all possible values of nn that make this statement true. This involves isolating nn on one side of the inequality, just as we would do when solving an equation. However, there's a crucial difference: when we multiply or divide both sides of an inequality by a negative number, we must reverse the direction of the inequality sign. This is because multiplying or dividing by a negative number changes the sign of the expressions, and to maintain the truth of the statement, we need to flip the comparison. For instance, if we have −2<4-2 < 4, multiplying both sides by -1 gives us 2>−42 > -4, illustrating the need to reverse the inequality sign. In the context of our problem, this means that when we eventually divide by the coefficient of nn, which is -5, we'll need to flip the inequality sign. Understanding this principle is essential for solving inequalities correctly. Without it, we risk arriving at an incorrect solution set. Another important concept to grasp is the representation of solutions to inequalities. Since inequalities often have a range of solutions, we can represent them graphically on a number line. This visual representation helps us understand the set of values that satisfy the inequality. We use open circles to indicate values that are not included in the solution set (for >> and <<) and closed circles to indicate values that are included (for ≥\geq and ≤\leq). With these foundational concepts in mind, we are now well-prepared to tackle the specific inequality at hand. Let's move on to the first step in solving 19≥4−5n19 \geq 4 - 5n: isolating the term containing the variable nn.

Step-by-Step Solution of 19≥4−5n19 \geq 4 - 5n

Now, let's embark on the journey of solving the inequality 19≥4−5n19 \geq 4 - 5n step by step. Our primary objective is to isolate the variable nn on one side of the inequality. This involves performing a series of algebraic operations while adhering to the rules of inequalities. The first step in isolating nn is to eliminate the constant term on the right side of the inequality. In this case, we have the constant 4 being added to the term −5n-5n. To remove this, we can subtract 4 from both sides of the inequality. This operation maintains the balance of the inequality, ensuring that the relationship between the two sides remains consistent. Subtracting 4 from both sides of 19≥4−5n19 \geq 4 - 5n gives us: 19−4≥4−5n−419 - 4 \geq 4 - 5n - 4 Simplifying this, we get: 15≥−5n15 \geq -5n Now, we have successfully isolated the term containing nn. The next step is to isolate nn itself. To do this, we need to eliminate the coefficient -5, which is multiplying nn. We can accomplish this by dividing both sides of the inequality by -5. However, as we discussed earlier, dividing by a negative number requires us to reverse the direction of the inequality sign. Dividing both sides of 15≥−5n15 \geq -5n by -5, we get: 15−5≤−5n−5\frac{15}{-5} \leq \frac{-5n}{-5} Notice that we have flipped the inequality sign from ≥\geq to ≤\leq. This is a crucial step in solving inequalities and ensures that we arrive at the correct solution. Simplifying the fractions, we get: −3≤n-3 \leq n This inequality tells us that nn is greater than or equal to -3. In other words, any value of nn that is -3 or greater will satisfy the original inequality 19≥4−5n19 \geq 4 - 5n. We can express this solution set in interval notation as [−3,∞)[-3, \infty). This notation indicates that the solution includes -3 and extends infinitely in the positive direction. To further solidify our understanding, let's verify our solution by substituting a value from our solution set into the original inequality. For example, let's choose n=0n = 0, which is clearly greater than -3. Substituting n=0n = 0 into 19≥4−5n19 \geq 4 - 5n, we get: 19≥4−5(0)19 \geq 4 - 5(0) 19≥419 \geq 4 This statement is true, confirming that our solution set is correct. We have successfully solved the inequality 19≥4−5n19 \geq 4 - 5n and found that n≥−3n \geq -3. This process highlights the importance of careful algebraic manipulation and the critical rule of reversing the inequality sign when multiplying or dividing by a negative number. Now, let's delve deeper into the interpretation of this solution and explore how it can be represented graphically.

Interpreting the Solution and Graphical Representation

Having arrived at the solution −3≤n-3 \leq n for the inequality 19≥4−5n19 \geq 4 - 5n, it's crucial to understand what this solution truly means and how it can be visually represented. The inequality −3≤n-3 \leq n tells us that the solution set includes all values of nn that are greater than or equal to -3. This means that any number that is -3 or larger will satisfy the original inequality 19≥4−5n19 \geq 4 - 5n. To visualize this solution set, we can use a number line. A number line is a simple yet powerful tool for representing inequalities graphically. It's a straight line with numbers marked at equal intervals, extending infinitely in both positive and negative directions. To represent the solution −3≤n-3 \leq n on a number line, we first locate -3 on the line. Since the inequality includes