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If ( array ll 2 & 3 4 & 1 array ) ( array cc 5 & -2 -3 & 1 array )= ( array cc 1 & -1 17 & array ) then what is equal to?

Options

  1. A7
  2. B–7
  3. C9
  4. D–9

Correct answer

B. –7

Step-by-step solution

aligned & | array ll 2 & 3 4 & 1 array | | array cc 5 & -2 -3 & 1 array |= | array cc 1 & -1 17 & array | & = | array cc 2 5-3 3 & -2 2+3 1 4 5-1 3 & -4 2+1 1 array |= | array cc 1 & -1 17 & array | & = | array cc 1 & -1 17 & -7 array |= | array cc 1 & -1 17 & array | & =-7 aligned

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