I like your graphical representation, thank you indeed. The cat actually starts from the middle of the room, which is at position 1.5 meters, but that's a technical detail, your graphs truly depict the opposing signs of accelerations. Thanks again!
Here I'm not worried about the solution as I got it. There are two ways I could come up with:
Either finding the time it takes the cat to leap through the window, use that time to find what distance does the dog cross through the room
Or: finding both times, for the dog and the cat to cross the...