2x-3y+4z=3, ①3x-2y+z=7, ②x+2y-3z=1, ③③×2-① 7y-10z=-1, ④③×3-② 8y-10z=-4, ⑤⑤-④ y=-3,代人④ 7×(-3)-10z=1, z=-2,代人③ x+2×(-3)-3(-2)=1,x=1.∴ x=1, y=-...