Question

http://prntscr.com/ddapyh

Answer 1

problem is in photo :)

Answer 2

@narissa

Answer 3

withch hone

Answer 4

\[2x+2z=4\]\[x+z=2\]\[-x-y-z=-y-(x+z)=-8\]\[-y-2=-8\]\[y=-2+8=6\]

Answer 5

\[-4x+4y+5z=7\]\[-4x+4*6+5z=7\]\[-4x+5z=7-4*6=-17\]

Answer 6

\[-4x+5z=-17\]\[x+z=2\]
So

Answer 7

\[x=2-z\]\[-4*(2-z)+5z=-17\]\[-8+4z+5z=-17\]\[9z=-17+8=-9\]\[z=-1\]\[x=2-z=2-(-1)=3\]

Answer 8

\[x=3\]\[y=6\]\[z=-1\]