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#