(12)2.5x+5.6-4.9=4.6x-1.4 (13)11-2.5(x-3)=10.5 (14)o.9+x=0.6(2.5-x) (15)2.4x+6.4=4x-4.8 (16)4.5×1.4-0,6x=2.1 (17)1.5(2x+o.4)=44-0.5x (18)8x-12.4=16(x-2.4) (19)3(x+2)=8(x-4) (20)72-4.5x=3(1.5x+12)