Đáp án:
Giải thích các bước giải:
$1)-\dfrac{5}{42}=-\dfrac{5}{6}.\dfrac{1}{7}$
$2)-\dfrac{5}{42}=\dfrac{5}{6}.-\dfrac{1}{7}$
$3)-\dfrac{5}{42}=-\dfrac{5}{7}.\dfrac{1}{6}$
$4)-\dfrac{5}{42}=\dfrac{5}{7}.-\dfrac{1}{6}$
$5)-\dfrac{5}{42}=-\dfrac{5}{2}.\dfrac{1}{21}$
$6)-\dfrac{5}{42}=\dfrac{5}{2}.-\dfrac{1}{21}$