(1/2)x+(x/3)π+(1/3)y+(y/2)π-4-π=0[(1/2)x+(1/3)y-4]+[(x/3)+(y/2)-1]π=0xy是有理数若(x/3)+(y/2)-1不等于0则[(x/3)+(y/2)-1]π是无理数(1/2)x+(1/3)y-4和0是有理数则等式不成立所以(x/3)+(y/2)-1=0则(1/2)x+(1/3)y-4也等于0两个等式分别乘62x+3y=63x+2y=24相减x-y=24-6=18