If P \(=\left[\begin{array}{cc}x+3 & x+2\\ x+1 & x-1\end{array}\right]\) evaluate x if |P| = -10

  • A -5
  • B -2
  • C 2
  • D 5
jamb 2009mathematics

The correct answer is D. 5

\(P=\left[\begin{array}{cc}x+3 & x+2\\ x+1 & x-1\end{array}\right]\)

evaluate x if |P| = -10

(x+3)(x-1) - {(x+1)(x+2)} = -10

x2 - x + 3x - 3 - {x2 + 2x + x + 2} = -10

x2 + 2x - 3 - {x2 + 3x + 2} = -10

-x - 5 = -10

-5 + 10 = x

5 = x

∴x = 5

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