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COMEDK2013MathematicsMatrices

What must be the matrix X if 2 X+ [ array ll 1 & 2 3 & 4 array ]= [ array ll 3 & 8 7 & 2 array ] ?

Options

  1. A[ array cc 1 & 3 2 & -1 array ]
  2. B[ array ll 1 & -3 2 & -1 array ]
  3. C[ array cc 2 & 6 4 & -2 array ]
  4. D[ array ll 2 & -6 4 & -2 array ]

Correct answer

A. [ array cc 1 & 3 2 & -1 array ]

Step-by-step solution

We have, 2 X+ [ array ll 1 & 2 3 & 4 array ]= [ array ll 3 & 8 7 & 2 array ] 2 X= [ array ll 3 & 8 7 & 2 array ]- [ array ll 1 & 2 3 & 4 array ] 2 X= [ array cc 2 & 6 4 & -2 array ] X= 1 2 [ array cc 2 & 6 4 & -2 array ]= [ array cc 1 & 3 2 & -1 array ]

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