解：2x+3y=k2(x+y)+y=k24+y=k ①3x+5y=k+23(x+y)+2y=k+236+2y=k+2 ②由①得y=k-24代入②36+2(k-24)=k+2k=14答：k的值是14。
2x+3y=k (1)3x+5y=k+2 (2)2(2)-(1)x+y=k-212=k-2k=14
