Solve the system 2x-y=-1 -2x+z=1 y-z=0

Unless you are required to solve it as a matrix/vector product, the simplest way is, from the 3rd, get y=z, substitute in the second and notice that the two equations are one and the same. You have solutions, given by the vector

+1,000)=g7e=mc2-g=7 because if you know algebra you should know g=7 to get your answer