Maths Olympiad Prep

Library / CEMC Pascal /125 of 603

CEMC Pascal, 2004

Algebra Difficulty 1.0 Junior Find the answer Canada

The symbol ∣abcd∣\begin{vmatrix} a & b \\ c & d \end{vmatrix} equals ad−bcad - bc. If ∣x−123−5∣=9\begin{vmatrix} x-1 & 2 \\ 3 & -5 \end{vmatrix} = 9, the value of xx is

(A) −4-4 (B) −3-3 (C) −2-2 (D) 22 (E) 44

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