Answer:
Wait
Step-by-step explanation:
do you need the value of x?
x=7+6y+2z
-2(7+6y+2z)+5y+2z=-1 -7y=13+2z
-14-12y-4z+5y+2z=-1
-14-7y-2z=-1
-7y-2z=-1+14
-7y-2z=13