题干

用配方法解方程x2-4x-5=0,下列配方结果正确的是(    )

A:x-42=21

B:x+42=21

C:x+22=9

D:x-22=9

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D

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    It was a late Wednesday night when the dreading phone call reached our home. I sat up, somehow terrified, so I could hear the phone call better. To my surprise, I heard my mom burst into tears. “Get the car, Dean! Andrea has been in a car accident.”

    We ran every stop sign on the way to the hospital and our tires screeched around every corner. We got to the hospital, but were not allowed to see Andrea. The next morning, after wearing masks, we were allowed to go to the ICU to see Andrea. Well, the least I could say was that everything was injured in her body and she lost all of her memories. It was a fatal accident.

    Over the next two months, I lived more at the hospital than I did at my house. I watched as Andrea worked so hard to gain back everyday motor skills. She never once complained or pitied herself; her determined spirit was shining through. After two weeks in the ICU and two months of the regular hospital treatment, Andrea was able to come home. She missed several months of school, so it was hard for her to catch up. Andrea had tasks to accomplish, and no matter how hard it was, she stuck with them until the job was done. Though busy with dealing with pain and therapy, she always found time to love and play with me.

    I'll never forget the impact that this incident made on my life. I admire her strong-willed personality and her determined spirit. Today she is perfectly normal, despite the scars and the pins holding her leg in place. I couldn't ask for a better sister, hero, or best friend.