Spade Operation
Source: AMC 12 2006B, Problem 2
February 17, 2006
AMC
Problem Statement
For real numbers and , define x\spadesuit y \equal{} (x \plus{} y)(x \minus{} y). What is ?
(A) \minus{} 72 \qquad (B) \minus{} 27 \qquad (C) \minus{} 24 \qquad (D) 24 \qquad (E) 72