Add or subtract a constant

Oct 13, 2025 by wbrum.org 39 views

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Introduction

Linear inequalities are a fundamental concept in mathematics, and they play a crucial role in various fields such as algebra, geometry, and calculus. In this article, we will focus on solving linear inequalities, with a specific emphasis on interval notation. We will explore the concept of interval notation, learn how to solve linear inequalities, and apply this knowledge to solve a given problem.

What is Interval Notation?

Interval notation is a way of representing a set of numbers using a specific notation. It is commonly used to represent the solution set of a linear inequality. In interval notation, a set of numbers is represented as an interval, which is a range of values between two endpoints. The endpoints can be included or excluded, depending on the context.

Types of Intervals

There are several types of intervals, including:

Open interval: An open interval is an interval that does not include its endpoints. It is represented as (a, b), where a and b are the endpoints.
Closed interval: A closed interval is an interval that includes its endpoints. It is represented as [a, b], where a and b are the endpoints.
Half-open interval: A half-open interval is an interval that includes one endpoint and excludes the other. It is represented as (a, b] or [a, b), where a and b are the endpoints.

Solving Linear Inequalities

To solve a linear inequality, we need to isolate the variable on one side of the inequality sign. We can do this by adding, subtracting, multiplying, or dividing both sides of the inequality by a constant. However, we need to be careful not to change the direction of the inequality sign when we multiply or divide both sides by a negative number.

Steps to Solve a Linear Inequality

Here are the steps to solve a linear inequality:

Isolate the variable: Move all the terms containing the variable to one side of the inequality sign.
Add or subtract a constant: Add or subtract a constant to both sides of the inequality to isolate the variable.
Multiply or divide by a constant: Multiply or divide both sides of the inequality by a constant to isolate the variable.
Check the direction of the inequality sign: If we multiply or divide both sides by a negative number, we need to change the direction of the inequality sign.

Solving the Given Problem

Now, let's apply the steps to solve the given problem:

Problem

Which interval is the solution set to $0.35x - 4.8 \ \textless \ 5.2 - 0.9x$ ?

Step 1: Isolate the variable

To isolate the variable, we need to move all the terms containing the variable to one side of the inequality sign. We can do this by adding $0.9x$ to both sides of the inequality:

$0.35x - 4.8 + 0.9x \ \textless \ 5.2$

Step 2: Combine like terms

Now, we can combine like terms on the left-hand side of the inequality:

$1.25x - 4.8 \ \textless \ 5.2$

Step 3: Add a constant

To isolate the variable, we need to add a constant to both sides of the inequality. We can do this by adding $4.8$ to both sides of the inequality:

$1.25x - 4.8 + 4.8 \ \textless \ 5.2 + 4.8$

Step 4: Simplify the inequality

Now, we can simplify the inequality by combining like terms:

$1.25x \ \textless \ 10$

Step 5: Divide by a constant

To isolate the variable, we need to divide both sides of the inequality by a constant. We can do this by dividing both sides of the inequality by $1.25$ :

$\frac{1.25x}{1.25} \ \textless \ \frac{10}{1.25}$

Step 6: Simplify the inequality

Now, we can simplify the inequality by dividing both sides by $1.25$ :

$x \ \textless \ 8$

Conclusion

The solution set to the given linear inequality is $(-\infty, 8)$ .

Conclusion

In this article, we learned how to solve linear inequalities using interval notation. We applied the steps to solve a given problem and found the solution set to be $(-\infty, 8)$ . We also discussed the concept of interval notation and the different types of intervals. We hope that this article has provided a clear understanding of how to solve linear inequalities and has helped you to develop your problem-solving skills.

Final Answer

The final answer is $\boxed{(-\infty, 8)}$ .

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Introduction

Linear inequalities are a fundamental concept in mathematics, and they play a crucial role in various fields such as algebra, geometry, and calculus. In our previous article, we discussed how to solve linear inequalities using interval notation. In this article, we will provide a Q&A guide to help you understand the concept of linear inequalities and how to solve them.

Q&A Guide

Here are some frequently asked questions about linear inequalities, along with their answers:

Q1: What is a linear inequality?

A1: A linear inequality is an inequality that involves a linear expression, which is an expression that can be written in the form ax + b, where a and b are constants and x is the variable.

Q2: How do I solve a linear inequality?

A2: To solve a linear inequality, you need to isolate the variable on one side of the inequality sign. You can do this by adding, subtracting, multiplying, or dividing both sides of the inequality by a constant. However, you need to be careful not to change the direction of the inequality sign when you multiply or divide both sides by a negative number.

Q3: What is interval notation?

A3: Interval notation is a way of representing a set of numbers using a specific notation. It is commonly used to represent the solution set of a linear inequality. In interval notation, a set of numbers is represented as an interval, which is a range of values between two endpoints.

Q4: What are the different types of intervals?

A4: There are several types of intervals, including:

Open interval: An open interval is an interval that does not include its endpoints. It is represented as (a, b), where a and b are the endpoints.
Closed interval: A closed interval is an interval that includes its endpoints. It is represented as [a, b], where a and b are the endpoints.
Half-open interval: A half-open interval is an interval that includes one endpoint and excludes the other. It is represented as (a, b] or [a, b), where a and b are the endpoints.

Q5: How do I determine the direction of the inequality sign?

A5: To determine the direction of the inequality sign, you need to consider the sign of the coefficient of the variable. If the coefficient is positive, the inequality sign is "greater than" or "greater than or equal to". If the coefficient is negative, the inequality sign is "less than" or "less than or equal to".

Q6: What is the solution set of a linear inequality?

A6: The solution set of a linear inequality is the set of all values of the variable that satisfy the inequality. It is represented in interval notation.

Q7: How do I graph a linear inequality?

A7: To graph a linear inequality, you need to graph the corresponding linear equation and then shade the region that satisfies the inequality.

Q8: What is the difference between a linear inequality and a quadratic inequality?

A8: A linear inequality is an inequality that involves a linear expression, while a quadratic inequality is an inequality that involves a quadratic expression.

Q9: How do I solve a system of linear inequalities?

A9: To solve a system of linear inequalities, you need to find the solution set of each inequality and then find the intersection of the solution sets.

Q10: What are some common mistakes to avoid when solving linear inequalities?

A10: Some common mistakes to avoid when solving linear inequalities include:

Changing the direction of the inequality sign when multiplying or dividing both sides by a negative number
Not isolating the variable on one side of the inequality sign
Not considering the sign of the coefficient of the variable

Conclusion

In this article, we provided a Q&A guide to help you understand the concept of linear inequalities and how to solve them. We hope that this article has provided a clear understanding of the concept of linear inequalities and has helped you to develop your problem-solving skills.

Final Answer

The final answer is $\boxed{(-\infty, 8)}$ .