Question

麻烦解个方程,2/(3-x)=(7-y)/(x-1)=(5-y)/4，麻烦求下x、y，

Answer 1

2/(3-x)=(5-y)/4→8=15-3y-5x+xy→5x-xy+3y=7------------------①

(7-y)/(x-1)=(5-y)/4→28-4y=5x-xy-5+y→5x-xy+5y=33----------②

②-①,得2y=26→y=13---------把y=3代入①,得5x-3x+9=7→2x=-2→x=-1

答案：X=-1,y=3