Đề kiểm tra học kỳ I môn Toán lớp 8 năm học 2014-2015 - THCS Bình Thành

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Bài 4: (3,0 điểm) Cho tam giác ABC cân tại A, đường cao AH. Gọi I là trung điểm của AB, K là điểm đối xứng với H qua I
a) Chứng minh tứ giác AHBK là hình chữ nhật.
b) Chứng minh: AC = HK
c) Tìm điều kiện của tam giác ABC để tứ giác AHBK là hình vuông.
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Bài 5: (1,0 điểm) Một đám đất hình chữ nhật có chiều dài 500m, chiều rộng 300m. Hãy tính diện tích đám đất đó theo đơn vị m2 , km2.
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