若x+2y+3z=10,4x+3y+2z=15,则x+y+z的值为(  ) A.2 B.3 C.4 D.5

问题描述:

若x+2y+3z=10,4x+3y+2z=15,则x+y+z的值为(  )
A. 2
B. 3
C. 4
D. 5

由题意,x+2y+3z=10①,4x+3y+2z=15②,
①+②,得:5(x+y+z)=25,即x+y+z=5;
故选D.