Đáp án:
$a)$
$x-1/5=7/11.3/21$
$=> x-1/5=1/11$
$=> x=1/11+1/5$
$=> x=16/55$
$b)x/25 = -3/15.7/6$
$=> x/25=-7/30$
$=> x=-7/30.25$
$=> x=-35/6$
$c) x:5/11=-4/12.6$
$=> x:5/11=-2$
$=> x=-2.5/11$
$=> x=-10/11$
$d) 7-|x+5|=1/6$
$=> |x+5|=7-1/6$
$=> |x+5|=41/6$
$=> x+5=41/6$ hoặc $x+5=-41/6$
$=> x=11/6$ hoặc $x=-71/6$
BẠN THAM KHẢO NHA!!!