7+x-3y/4=2x-y+5/3同时乘以12化为整数:84+12x-9y=24x-12y+2012x-3y=64;(a)10(x-y)-4(1-x)/3=y同时乘以3化为整数:30(x-y)-4(1-x)=3y30x-30y-4+4x-3y=034x-33y=4;(b)a式*11-b式:132x-33y-(34x-33y)=704-498x=700x=0.14,y=-20.773~