Có 1 bài nên mình cho ít điểm, các bạn thông cảm Cho tam giác ABC vuông tại A có điểm H chuyển động trên BC; E,F lần lượt là điểm đối xứng của H qua AB,AC. a, chứng minh E,A,F thẳng hàng. b,chứng minh BEFC là hình thang. c,tìm vị trí của H trên BC để BEFC là hình thang vuông. d,Nếu tam giác ABC vuông cân tại A, H là trung điểm của BC chứng minh BEFC là hình thang vuông.

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Participants (n) Decision (n) Volunteer (n) Poverty (n) Community (n) Difference (n) Family (n) Opportunities (n) Interview (n) Participation (n) Dear Volunteer, Welcome to our team! Thank you for choosing to become a member of our (16)________! We are delighted to have you as part of our dynamic, caring team! “Action for a Better Community” (ABC) was founded more than 45 years ago. In the beginning, ABC was one of hundreds of “community action agencies”, established in communities throughout the United States to help low-income people. We started with small amounts of money with a strong determination to help people break the cycle of (17)_________ and achieve self-sufficiency. ABC has made a (18)________ for over 35,000 children and families served through the Head Start programme. Your (19_________ as a volunteer is especially important as we move in the future with a focus on child development services, employment and training, housing, and health (especially AIDS/HIV-related education and counseling). (20)_________ jobs range from direct service to our programme (21)_________ to agency leadership as members of our Board of Directors. Together you bring your range of skills, experience and dedication to support ABC’s vital work in our (22)_______. We promote and provide (23)__________ for low-income individuals and families to become self-sufficient. Your (24)________, placement and orientation are important first steps. Your (25)_________to help ABC in order to help people help themselves is greatly appreciated! Sincerely, James H. Norman President & CEO