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34 votes
Find the real solutions of 9-l2xl=2

User Pontus
by
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1 Answer

19 votes
19 votes

Answer

x = -7/2, 7/2

Explanation

Given the equation:


9-|2x|=2

Subtracting 9 at both sides of the equation:


\begin{gathered} 9-9-\lvert2x\rvert=2-9 \\ -\lvert2x\rvert=-7 \end{gathered}

Dividing by -1 at both sides of the equation:


\begin{gathered} (-\lvert2x\rvert)/(-1)=(-7)/(-1) \\ |2x|=7 \end{gathered}

Now we have two options:


\begin{gathered} 2x=7 \\ \text{ Or} \\ 2x=-7 \end{gathered}

Solving the first option:


\begin{gathered} 2x_1=7 \\ (2x_1)/(2)=(7)/(2) \\ x_1=(7)/(2) \end{gathered}

Solving the second option:


\begin{gathered} 2x_2=-7 \\ (2x_2)/(2)=(-7)/(2) \\ x_2=-(7)/(2) \end{gathered}

User Kaveesh Kanwal
by
2.6k points