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5 votes
Solve the equation. 5 | n | - 15 = 40

User Deeshank
by
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2 Answers

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|a|=\left\{\begin{array}{ccc}a&amp;for&amp;a\geq0\\-a&amp;for&amp;a<0\end{array}\right\\\\Examples:\\|2|=2\\|1,234|=1,234\\|0|=0\\|-6|=-(-6)=6\\|-102|=-(-102)=102\\|-3,456.7|=3,456.7\\----------------------------\\5|n|-15=40\ \ \ |+15\\\\5|n|=55\ \ \ |:5\\\\|n|=11\Rightarrow n=\pm11\ \text{because}\ |-11|=11\ \text{and}\ |11|=11

Answer: n = -11 or n = 11

User Ryeager
by
4.6k points
5 votes
Hi there!

Let's solve this equation step by step!


5 |n| - 15 = 40
First add 15 to both sides of the equation.


5 |n| = 55
Now divide both sides by 5.


|n| = 11

Finally we need to take a look at the meaning of the stripes between our variable. Those stripes mean we are dealing with an absolute value function. The absolute value stripes make everything between the stripes positive; also when we plug in a number. In this particular question we can plug in both -11 and 11 at the position of n, because when -11 is made positive, it fulfils the equation.

Hence,

n = 11 or
n = - 11

~ Hope this helps you!
User Sorade
by
5.3k points
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