If x and y are non-zero integers and |x| + |y| = 32, what is xy?
(1) -4x – 12y = 0
(2) |x| – |y| = 16
(1) -4x – 12y = 0
(2) |x| – |y| = 16
Smashed the GMAT: 760
(1) -4x – 12y = 0 SUFFICIENT
or x + 3y = 0, or x = -3y. So we know that x and y will have different signs. And the result will be -1*|x|*|y|. Solve the equations to get |x| = 24 and |y| = 8, thus making xy = -192
(2) |x| – |y| = 16 INSUFFICIENT
we will be able to calculate |x| = 24 and |y| = 8. but the result can be -192 or 192
