Solving Absolute Value Problem: x ≤ 3

In summary, the conversation discusses how to solve the absolute value equation | x-3 | = 3 – x and how to verify the solutions. It is mentioned that the equation has two solutions, one being 3 and the other being all real numbers. However, it is explained that the second solution does not satisfy the equation when verified. The confusion arises when the book's answer is given as x <= 3, which is explained by the fact that in order for the equation to be satisfied, 3 - x must be greater-than-or-equal-to zero. This leads to the solution of x = 3.
  • #1
ziaharipur
6
0
Suppose we have this absolute value question | x-3 | = 3 – x
If we solve this question we break it as
X - 3 = 3 – x or -(x - 3) = 3 - x
Now if we solve it we come to know that the part on right is true for all real numbers
And the part on the left is true for only 3

I also have read that if there is a variable on right side of absolute value then we need to verify our solutions.
Now we have two solution one is 3 and the other one is all real numbers. The first solution works but there is a problem with the second one, Suppose we have a real number 4 and we put it in our absolute value equation

| x – 3 | = 3 – x
| 4 – 3 | = 3 – 4
| 1 | = -1
Now when we verify our solution we discard the solution not satisfying the equation as in this case the second solution is not satisfying the solution. So, we have only one solution to this equation and that is 3.

But when I saw the answer of this question in the book I saw that the answer is x < =3

Now I am confuse please help me.
 
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  • #2
Notice that in order for the equation

[tex]
|x -3| = 3 - x
[/tex]

to be satisfied, [itex] 3 - x [/itex] must be greater-than-or-equal-to zero, since the left side of the equation is. Do you see how that fact leads to the solution?
 

FAQ: Solving Absolute Value Problem: x ≤ 3

What is the definition of absolute value?

The absolute value of a number is the distance of that number from zero on a number line. This means that the absolute value is always positive, regardless of whether the original number is positive or negative.

How do you solve an absolute value inequality?

To solve an absolute value inequality, you must first isolate the absolute value expression on one side of the inequality. Then, you can remove the absolute value bars and create two separate equations, one with a positive sign and one with a negative sign. Solve both equations and combine the solutions to find the final solution set.

What does the solution set for x ≤ 3 look like?

The solution set for x ≤ 3 represents all values of x that are less than or equal to 3. This can be represented on a number line by shading in the region to the left of 3, including the point 3 itself.

Can the solution set for an absolute value inequality be empty?

Yes, the solution set for an absolute value inequality can be empty. This would occur if the absolute value expression results in a contradiction, such as |x| < -2. In this case, there are no values of x that would satisfy the inequality.

How can you check your solution to an absolute value inequality?

To check your solution, you can substitute the values from the solution set into the original absolute value inequality. If the resulting statement is true, then the solution is correct. If it is false, then you should recheck your work to find where you made a mistake.

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