The answer is positive 1/5. Here is a tip, when reading a graph read from left to right. If it is going up to the right it is positive. If it goes down going to the right it is negative. Also think rise/run. Count how many times it goes up(or down) then count how long the line goes.
I think it’s C but what grade is this
You don't need 3 equations to get a general solution. To do this use the equations x-3y-z=0 and -x+2y+0z= -3. Start out by letting z = t. Then solving those 2 equations simultaneously, your x's cancel out leaving you with -y-z=-3. But since z=t, then -y=-3+t or y=3-t. Now sub that in for y in the first equation, along with the fact that z=t to get x-3(3-t)-t = 0 and solve for x. x=9-2t. So a general solution for this would be (9-2t, 3-t, t)