CEMC Fermat, 2010

Algebra Difficulty 1.0 Junior Find the answer Canada

The value of $k\nabla m$ is defined to be $k(k - m)$ . For example, $7\nabla 2 = 7(7-2) = 35$ . What is the value of $(5\nabla 1) + (4\nabla 1)$ ?

(A) $9$ (B) $84$ (C) $20$ (D) $32$ (E) $72$

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