How do you solve $-63= - 9| w |$ ?

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Answer 1 · 2018-05-09T15:05:15

$color(blue)(w=+-7)$

$-63=-9|w|$

First divide both sides by $-9$

$|w|=7$

By the definition of absolute value:

$|a| = acolor(white)(8888.8)bb("if and only if")color(white)(888) a>=0$

$|a| = -acolor(white)(888)bb("if and only if")color(white)(888) a < 0$

Because of this we need to solve both:

$w=7$

and

$-(w)=7$

$:.$

$w=7 and w=-7$

$w=+-7$

How do you solve -63= - 9| w |-63= - 9| w |?