题目

    HOUSE FOR SALE. Comfortable family house with a large garden on north side of town. Three bedrooms, living-room, kitchens, dining-room, bathroom. Offers over 35000 dollars.     ASSISTANT WANTED FOR BUSY RESTAURANT. Some evening and weekend work. All meals free. Ring 3320178.     JOIN OUR FOOTBALL TEAM. Boys and girls wanted to play in a local football team. Aged 9-13. Meet in Green Park on Friday at 3 p.m.     ROOM TO RENT. Small room to rent in city center flat above restaurant. Newly painted with modern furniture. Near main railway station. Buses pass front door. Phone 332210已知方程组的解满足x、y都为负数．（1）求a的取值范围；（2）化简：|a-4|-|a+3|．