Question

x+y=-14 y+z=-7 x+z=19三元一次方程组的解

Answer 1

x+y=-14.(1)

y+z=-7 .(2)

x+z=19.(3)

三式相加,得

2x+2y+2z=-2

x+y+z=-1.(4)

(4)-(1)得

z=13

(4)-(2)得

x=6

(4)-(3)得

y=-20

解得

x=6

y=-20

z=13