x-(x-1)=7-(x+3)/5x-x+1=7-x/5+3/5x/5=7-3/5-1x/5=27/5x=27.只是第一题的解,后面自己想吧..
(1)X=-2/3;(2)X=9;(3)X=20;(2)X=-81/77;
(0.5+1.3)x=6.5+0.71.8x=7.2x=4