"Decreasing" rate means - sign?

Hi again all,

I answered a related rates type problem from a Calc final and the solution sheet's answer was +6 where my answer was -6:

The equation of a curve in the plane is e^(xy) = x^2 +y^2

A particle is moving along this curve at a certain velocity. At the instant that

it moves through the point (0, 1) the y coordinate is decreasing

at the rate of 3 cm/sec. How fast is the x coordinate changing

at this instant and is it increasing or decreasing.

I interpreted dy/dt as -3 cm/sec but in their answer sheet they marked it as 3, so would I get marks off for something like this?