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What does this mean 3|-3| the whole |-3| thing I'm confused please help ​

User JD Courtoy
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|-3| means "the absolute value of 3", which is a way of saying how far away from zero the number -3 is on the number line.

The definition of absolute value goes like this:


|x| = \begin{cases} x &amp; \text{if } x \ge 0 \\ -x &amp; \text{if } x < 0 \end{cases}

In other words, if the number
x inside the absolute value bars is already positive or zero, we leave it alone. If instead
x is negative, we multiply it by -1 to recover the positive version of that number.

Since -3 is negative, it follows that |-3| = -(-3) = 3. So the expression 3 |-3| is equivalent to 3 • 3 = 3² = 9.

User That Dave Guy
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