x = -7, y = 6, z = 3
First, you should try to find 2 equations where there are only two variables. So, I cancelled out the z variable and made 2 equations that only included x and y.
Then, I used a system of equations again to solve for y, then I plugged in y to find x.
Then, finally you can plug in x and y into one of the original equations to find z.
All my steps are in the photo, if you have any other questions let me know!