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39 votes
39 votes
Solve for x: |2x + 12| = 18Group of answer choicesx = 3, x = −3x = 3, x = −15x = 15, x = −15x = −3, x = 15

User Aniruddh Agarwal
by
3.1k points

1 Answer

13 votes
13 votes

The problem is given to be:


|2x+12|=18

Step 1: Apply the Absolute Rule stated below:


\begin{gathered} If \\ |u|=a \\ \text{then} \\ u\: =\: a\: \quad \mathrm{or}\quad \: u\: =\: -a \end{gathered}

Therefore, we have:


\begin{gathered} 2x+12=18 \\ or \\ 2x+12=-18 \end{gathered}

Step 2: Solve the first case:


\begin{gathered} 2x+12=18 \\ Subracti\text{ng 12 from both sides:} \\ 2x=18-12 \\ 2x=6 \\ \text{Dividing both sides by 2:} \\ x=(6)/(2) \\ x=3 \end{gathered}

Step 3: Solve the second case:


\begin{gathered} 2x+12=-18 \\ \text{Subracting 12 from both sides:} \\ 2x=-18-12 \\ 2x=-30 \\ Divid\text{ing both sides by 2:} \\ x=(-30)/(2) \\ x=-15 \end{gathered}

ANSWER:

The values of x are:


x=3,x=-15

User Sambro
by
2.9k points
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