Lời giải:
Báo sai\(\begin{array}{*{20}{l}} {\left( { - 2019} \right) + ( - 21 + 75 + 2019)}\\ { = ( - 2019 + 2019) + (75 - 21)}\\ { = 0 + 54}\\ { = 54} \end{array}\)
ADMICRO
YOMEDIA
ZUNIA9