Absolute value equation

How do you solve |-3r| = 9 ?

Absolute Value means distance from zero. 

|-3r| = 9 is saying -3r is 9 away from zero. 

The two numbers that are 9 away from zero are 9 and -9. 

-3r = 9 or -3r = -9   {set -3r equal to 9 and -9}
r = -3  or  r = 3   {solved for r}

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