# How do you simplify  -abs(8+9-21)?

Jun 8, 2016

We can simplify the expression to $- 4$

## $\textcolor{l i g h t b l u e}{\text{How?}}$

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- First we add the numbers inside $| |$
$\implies$ $8 + 9 - 21 = 17 - 21 \implies - 4$

Now we are left with $- | - 4 |$

We have to apply absolute rule which is $| - a | = a$

$| - 4 | = 4$

We sill have $-$

$- | - 4 | \implies - 4$

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That is all, easy right? $\textcolor{g r e e n}{\text{✔}}$