1.4/(x+5)+1/(y-2)=4
问题描述：
1.4/(x+5)+1/(y-2)=4
2/(x+5)+1/(2-y)=8
2.(x+y)/3-3/(x-y)= -1/6
(x+y)/2+2/(x-y)=3
3.1/x+1/y=1/10
1/y+1/z=1/15
1/z+1/x=1/12
4.x/2=y/-3=z/4
x/(x+y+z)=2/(4x-5)
答
1.解 4/(x+5)+1/(y-2)=4 ①2/(x+5)－1/(y-2)=8 ②两者相加得,6/（x＋5）=12得x=－4.5代入式①得y=1.75 2、解 (x+y)/3-3/(x-y)= -1/6 ①(x+y)/2+2/(x-y)=3 ② ①/2-②/3,得：-(3/2+2/3)/(x-y)=-13/12 得：x-y=2 ③；2...