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Need help with this. This is all one problem. The directions are numbered 1-6

Need help with this. This is all one problem. The directions are numbered 1-6-example-1
Need help with this. This is all one problem. The directions are numbered 1-6-example-1
Need help with this. This is all one problem. The directions are numbered 1-6-example-2
User Darkhorse
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1 Answer

20 votes
20 votes

Given the inequality:


2-|3x-5|>-7

To find x, follow the steps below.

Step 01: Isolate the absolute value.

To do it, first, subtract 2 from both sides of the inequality.


\begin{gathered} 2-|3x-5|-2>-7-2 \\ 2-2-|3x-5|>-9 \\ -|3x-5|>-9 \end{gathered}

Now, multiply the equation by -1:


|3x-5|<9

If |3x - 5| < 9, then 3x - 5 < 9 or -(3x - 5) < 9.

Step 02: Find the interval in which 3x - 5 < 9.


3x-5<9

Isolate x by adding 5 to both sides. In sequence, divide the sides by 3:


\begin{gathered} 3x-5+5<9+5 \\ 3x<14 \\ (3x)/(3)<(14)/(3) \\ x<(14)/(3) \end{gathered}

Step 03: Find the interval in which -(3x - 5) < 9.


-3x+5<9

To isolate x, first, subtract 5 from both sides. Second, divide the sides by 3. Finally, multiply the inequality by -1.


\begin{gathered} -3x+5-5<9-5 \\ -3x<4 \\ (-3x)/(3)<(4)/(3) \\ -x<(4)/(3) \\ x>-(4)/(3) \end{gathered}

Step 04: Graph the interval.

Since x < 14/3 and x > -4/3:

Graphing the answer:

Step 05: Write your answer in interval notation.


-(4)/(3)In interval notation: <p></p>[tex](-(4)/(3),(14)/(3))

Step 06: Double-check the solution.

To double-check the solution, choose one point inside the interval and observe if the answer fits the equation. You can also choose a point outside the interval.

Let's choose x = 0 (inside the interval) and x = 5 (outside the interval).


\begin{gathered} 2-|3x-5|>-7 \\ \end{gathered}

Substituting x by 0.


\begin{gathered} 2-|3\cdot0-5|>-7 \\ 2-|0-5|>-7 \\ 2-|5|>-7 \\ 2-5>-7 \\ -3>-7 \end{gathered}

True.

Substituting x by 5.


\begin{gathered} 2-|3x-5|>-7 \\ 2-|3\cdot5-5|>-7 \\ 2-|15-5|>-7 \\ 2-|10|>-7 \\ -8>-7 \end{gathered}

False, since -8 is not greater than -7. It is expected since 5 is not an answer for this inequality.

Answer:


(-(4)/(3),(14)/(3))

Need help with this. This is all one problem. The directions are numbered 1-6-example-1
User Grishma
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