I was given three planes:
$$x + y + 6z = 4$$
$$x + 2y + 8z = 7$$
$$2x + 4y + 16z = 15$$
The question first asked to convert these into a coefficient matrix. Secondly it asked me to use Gaussian elimination to solve the matrix equation. The solution i got was $(2, 11/4, 1/8)$. The third part is where i get confused. it asks me to write down the matrix that produces the first row operation in my solution to part b. What is this question asking me to do.?