Question

x+y+z=100与10x+5y+0.5z=100

属于二元二次方程吗？告诉我怎样解？

Answer 1

属于三元一次方程,2(10x+5y+0.5z)=20x+10y+z=200 (20x+10y+z)-(x+y+z)=200-100=100 19x+19y=100 x+y=100/19 z=100-100/19 5(x+y+z)=500 (10x+5y+0.5z)-5(x+y+z)=5x-0.5z=100-500=-400 x=(-400+0.5z)/5=[-400+0.5(100-100/19)]/5=[-400+50-50/19]/5=-80+10-10/19=-70-10/19x+y+z=-70-10/19+y+(100-100/19)=100y=100-(-70-10/19)-(100-100/19)=100+70-100+10/19+100/19=70+110/19

Answer 2

这是三元一次方程式