已知关于x，y的二元一次方程（a﹣1）x+（a+2）y+5﹣2a=0，当a每取一个值时，就有一个方程，而这些方程有一个公共解，试求出这个公共解．

2011年美国东部时间5月16日上午8时56分，高精度粒子探测器——“阿尔法磁谱仪”陪伴美国“奋进”号航天飞机的“绝唱之旅”，驶入寰宇．未来10年或更长时间里，它将在国际空间站运行，寻找反物质和暗物质，探索宇宙起源及其构成．“阿尔法磁谱仪”的“保暖外衣”热系统由山东大学科学家领衔研制，是人类史上首次解决带电磁铁在太空中运行的温度控制问题．鲜为人知的是，它体内有一颗强大的“中国心”——一内径约1.2米、重约2.6吨、中心磁场强度1370高斯的环形巨大永磁铁．.下列相关的说法中正确的是（      ）

    Tennis Court

    Located in our neighboring island, enjoy a short boat ride to reach the tennis court. An all-weather exterior(外面的) court provided an exceptional playing surface for a great game of singles or doubles. Free tennis equipment is available.

    Time: Open daily 8:00 am to 8:00 pm

    Hitting partner is available at US$ 65 per hour per person.

    Reservation in advance is required. Please contact Recreation.

    Price should include an extra 20% service charge.

    Fitness Centre

    Located near the main pool, our fitness centre Kuda Hurra provides physical challenges and mental relaxation.

    Guests must be at least 13 years of age to use the facility. Free athletic wear is available while a Fitness Centre Attendant provides assistance only from 7:00 am to 9:00 pm. For the safety of everyone using the facility we request that no children under the age of 18 are permitted to use the facility when unattended by our staff.

    Open 24 hours.

    Kids for all seasons

    Children from four to twelve years are welcome to join our Kids for All Seasons Programme. The Kids Club is located near the main pool next to the Gym building and is open daily from 9:00 am to 5:00 pm.

    The Kuda Mas Club includes recreational and educational activities such as arts and crafts, painting, leaf folding, island discovery tours, fish feeding and much more.

    Please contact the Kuda Mas Club for more information.