Maths Olympiad Prep

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CEMC Fermat, 2001

Algebra Difficulty 1.0 Junior Find the answer Canada

If 5+11−7=5+11−x\sqrt{5+11-7} = \sqrt{5+11} - \sqrt{x}, then the value of xx is

(A) 11 (B) 77 (C) −7-7 (D) 4949 (E) 44

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