Linear Algebra Vector Equation???

Question

The only question on my review that I don't know how to solve.

 

 

Solve for x:

 

          [ 6 ]
4x +   [ -3 ]  = x
         [ -9 ]  

 

 

 

key note :    [ 6 ]

                   [ -3 ]     is represent as  a 3 x 1 matrix    

                   [ -9 ]

 

Answer 1

Presumably x is also a 3 x 1 matrix, so I think what you mean must be the following:

 

Subtract x from both sides, and you get:

 

        [ 6 ]
3x + [ -3 ] = 0
        [ -9 ]

 

        [ -6 ]
3x =  [ 3 ]
        [ 9 ]

 

x = [-2]

      [ 1]

      [ 3]