Chapter 2: Problem 5
Graph each inequality on a number line. Then write the solutions in interval notation. $$ x \leqq-1 $$
Short Answer
Expert verified
\(( -\infty, -1 ]\)
Step by step solution
01
Understanding the Inequality
First, let's interpret the inequality \( x \leq -1 \). This means that \( x \) can be any number less than or equal to \(-1\). The values of \( x \) include all numbers to the left of \(-1\) on the number line, including \(-1\) itself.
02
Graph the Inequality
To graph \( x \leq -1 \) on a number line, draw a closed circle (or dot) on \(-1\) to indicate that \(-1\) is included in the solution. Then shade the number line to the left of \(-1\) to show all the numbers that are less than \(-1\).
03
Write in Interval Notation
In interval notation, the solution ensures that \( x \) includes \(-1\) and all numbers less than \(-1\). This is represented as \(( -\infty, -1 ]\), where \(-\infty\) is used to indicate that there is no lower bound and the \([\; ]\) bracket means \(-1\) is included in the set.
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.
graphical representation of inequalities
Graphical representation of inequalities is a powerful visual tool that allows us to easily interpret and understand the range of solutions for an inequality. When you graph an inequality like \( x \leq -1 \) on a number line, the first thing you need to do is identify the boundary point, which in this case is \,\(-1\).
Here's how you do it:
Here's how you do it:
- Locate the number \(-1\) on the number line.
- Place a closed circle (filled dot) on \(-1\) to indicate that this number is included in the solution set. The closed circle signifies that \(-1\) is part of the solution because we are dealing with ''less than or equal to''.
- Shade the entire part of the number line to the left of \(-1\). This shaded region represents all the numbers that are less than \(-1\).
interval notation
Interval notation is a compact and efficient way to express a range of numbers, and it is especially useful for representing solutions to inequalities. In the inequality \( x \leq -1 \), we need to describe all the possible values of \( x \) that satisfy this condition.
Here's how interval notation works:
Here's how interval notation works:
- Starts with a parenthesis ''('' or a bracket ''['' and ends with a parenthesis '')'' or bracket '']''. Use a parenthesis to indicate that a number is not included (open interval) or a bracket when it is included (closed interval).
- For \( x \leq -1 \), the interval notation is \((-\infty, -1]\). The parenthesis with \(-\infty\) indicates the interval extends indefinitely to the left, meaning there is no minimum value. The bracket with \(-1\) shows that this value is contained within the interval.
solving linear inequalities
Solving linear inequalities is similar to solving equations, but there are a few extra rules to remember. When you solve an inequality, you're looking for the set of values that makes it true.
Here are the simple steps:
Here are the simple steps:
- Identify the inequality you need to solve; for example, \( x \leq -1 \).
- Think about what values of \( x \) make this inequality true. For example, any number that is \(-1\) or less satisfies \( x \leq -1 \).
- Solve the inequality as you would a simple equation, but keep in mind that if you multiply or divide by a negative number, the inequality sign flips direction. Luckily, we don't need to do that here.