||x+3|-19=0
=> |x+3|-19=0
=>|x+3| =19
=>x-3=19 hoac x-3=-19
TH1: x+3=19 TH2: x+3=-19
x =19+3 x =-19+3
x = 22 x = -16
Vay x thuoc {-16,22}
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