Chapter 2: Problem 112
Graph the solution set, and write it using interval notation \(-4<2(x+1) \leq 6\)
Short Answer
Expert verified
The solution in interval notation is \((-3, 2]\).
Step by step solution
01
- Simplify the inequality
First, simplify the inequality by distributing the 2 on the right side: \(-4 < 2(x + 1) \leq 6\) becomes \(-4 < 2x + 2 \leq 6\).
02
- Isolate the variable term
Next, subtract 2 from all parts of the inequality to get all terms involving x isolated on one side: \(-4 - 2 < 2x + 2 - 2 \leq 6 - 2\) Simplifying, we get: \(-6 < 2x \leq 4\).
03
- Solve for x
Divide every part of the inequality by 2 to solve for x: \(\frac{-6}{2} < \frac{2x}{2} \leq \frac{4}{2}\) Simplifying, we get: \(-3 < x \leq 2\).
04
- Write the solution in interval notation
The solution in interval notation is written as the set of x values that satisfy the inequality: \((-3, 2]\).
05
- Graph the solution set
Graph the solution set on a number line. Use an open circle at -3 to indicate that -3 is not included in the solution set, and a closed circle at 2 to indicate that 2 is included. Shade the region in between. The graph looks like this:Open circle on -3, closed circle on 2, and shading between them.
Unlock Step-by-Step Solutions & Ace Your Exams!
-
Full Textbook Solutions
Get detailed explanations and key concepts
-
Unlimited Al creation
Al flashcards, explanations, exams and more...
-
Ads-free access
To over 500 millions flashcards
-
Money-back guarantee
We refund you if you fail your exam.
Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!
Key Concepts
These are the key concepts you need to understand to accurately answer the question.
Interval Notation
Interval notation is a simple way of expressing a range of values. Instead of writing all the possible values individually, you can write a compact representation. For example, \((-3, 2]\) means that x can be any value between -3 and 2, but -3 itself is not included, while 2 is.
In interval notation:
This notation makes it clear and easy to understand the range of values that satisfy our inequality.
In interval notation:
- Round brackets \(( )\) indicate that the endpoint is not included.
- Square brackets \[ ]\] indicate that the endpoint is included.
This notation makes it clear and easy to understand the range of values that satisfy our inequality.
Inequality Graph
Graphing inequalities on a number line helps visualize the set of possible solutions. In this case, our solution set is \(-3 < x \leq 2\).
This interval means that x is greater than -3 but less than or equal to 2.
Here’s how to graph the solution set:
This interval means that x is greater than -3 but less than or equal to 2.
Here’s how to graph the solution set:
- Draw a number line.
- Place an open circle at -3 to show that -3 is not included.
- Place a closed circle at 2 to show that 2 is included.
- Shade the region between -3 and 2.
Variable Isolation
Isolating the variable is a critical step in solving inequalities. It involves simplifying the inequality until the variable is alone on one side. Here’s how we did it:
First, we started with the inequality \(-4< 2(x + 1) \leq 6\).
First, we started with the inequality \(-4< 2(x + 1) \leq 6\).
- We distributed the 2: \(-4 < 2x + 2 \leq 6\).
- Next, we subtracted 2 from each part of the inequality: \(-6 < 2x \leq 4\).
- Finally, we divided each part by 2: \(-3 < x \leq 2\).
Solving Inequalities
Solving inequalities is similar to solving equations, but with an added focus on the inequality signs. Follow these key steps:
This isn’t needed here, but it’s crucial in other problems.
- Start with the given inequality: \(-4< 2(x + 1) \leq 6\).
- Distribute any numbers outside parentheses: \(-4 < 2x + 2 \leq 6\).
- Subtract or add terms to isolate the variable: \(-6 < 2x \leq 4\).
- Divide or multiply to solve for the variable: \(-3 < x \leq 2\).
- Write the solution using interval notation.
This isn’t needed here, but it’s crucial in other problems.