How do i find the missing column of a matrix given the full RREF form?

[Incognitopad]

Homework Statement

I'm given a 4x5 matrix with one missing column. I'm also given the RREF form with no missing columns.

Previous parts of the question made me find the row, column, and null basis for the matrix.

Now it's asking:

d) Find the missing column. (Hint: Are the columns of the matrix linearly independent or dependent?)

How would I go about finding the missing column? ^ What is the hint trying to get me to do? :s,

The rank of the RREF is 3, by the way.

Homework Equations

The Attempt at a Solution

 

[Incognitopad]

bump :(