I don't understand it

Solve the system of equations by any method. 3x - 4y + 2z = -22 2x + 4y + z = 18 2x + 3y + 5z = 21 Enter the exact answer as an ordered triple, (z, y, z). Hint: There are multiple ways to solve this system of equations. . A strategy is to eliminate one of the variables and end up with 2 equations in 2 variables. . One way to do that is to begin with equation 2 to get z = 18 - 2 x - 4y. . Then substitute 18 - 2 x - 4 y for z in equations 1 and 3. . You now have 2 equations (the modified equations 1 and 3) in 2 variables (x and y). . Solve this smaller system for a and y and then use z = 18 - 2 x -4 y to calculate z. Nett