(1)去括號(hào),得
a-
-2-a=2,
去分母,得a-4-6-3a=6,
移項(xiàng),合并得-2a=16,
化系數(shù)為1,得a=-8;
(2)去分母,得5(x-3)-2(4x+1)=10,
去括號(hào),得5x-15-8x-2=10,
移項(xiàng)、合并得-3x=27,
化系數(shù)為1,得x=-9;
(3)把分母化為整數(shù),得
-
=2,
去分母,得5(10x+40)-2(10x-30)=20,
去括號(hào),得50x+200-20x+60=20,
移項(xiàng)、合并得30x=-240,
化系數(shù)為1,得x=-8.