Question 853991
What method do you want to use?  Try substitution if this is allowed for your class right now.


z=3-x from the first equation.  The next two equations using this substitution are:
x+2y-(3-x)=1 and 2x-y+(3-x)=3;
2x+2y-3=1 and x-y+3=3;
2x+2y=4 and x-y=0;
x+y=2 and x-y=0;
Using simple elimination, adding left members and adding right members gives:
2x=2 which means x=1.  This also means, using x-y=0 that y=1.


Use the first equation now to find the value for z.