If 4x+y+z=800, 2x-y-z=40,3x+y-z = 12 for integers of x,y and z, find z =?
Choices:
A) 250 B) 464 C) 525 D) 256 E) 324
4x+y+z = 800----------1)   2x-y-z = 40-------------2)   3x+y-z = 12 ------------3)   from 1) and 2)   6x = 840   x = 140 substitute in 1) and 3)   560+y+z = 800   y+z = 240-------4)   420+y-z = 12   y-z = -408-------5)   from 4) and 5)   2z = 648   z = 324   Answer is 324
<result>E</result>
If 4x+y+z=800, 2x-y-z=40,3x+y-z = 12 for integers of x,y and z, find z =?