Add and Subtract Matrices

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What must be true in order to ADD two matrices?

• They must be square.

• The dimensions must be equal.

• The determinant can't equal 0.

• The column of the 1st must equal the row of the 2nd.

Add

• 11    8
  -4     2

• 3     2
  -6    -6

• -3    2
  -4    -6

• 10    8
  -6    2

What do w, x, y and z equal in this matrix subtraction?

• w = 13, x = 4, y = 7, z = 23

• w = 13, x = -4, y = 11, z = 23

• w = 13, x = 4, y = 11, z = 23

• w = 13, x = 4, y = 11, z = 17

Given these matrices find C - D

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• NA

Find B-A

• -4     0
  6     -1

• 1     0
  1     -4

• 4       0
  -6     1

• not possible because rows do not match columns

Find Z - W

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• Does Not Exist

• A

• B

• C

• D

Given these matrices find D - A

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• NA

• A

• B

• C

• D