KIEM TRA 1 TIET CHUONG 3 TU LUAN CO D AN

PHÒNG GD&ĐT HƯỚNG HOÁ
TRƯỜNG THCS TÂN LIÊN



ĐỀ KIỂM TRA 1 TIẾT - TUẦN 27 - NĂM HỌC 2009-2010
MôN: TOÁN ( HÌNH HỌC) - LỚP 8
Thời gian 45`phút ( kể cả thời gian giao đề )


Họ và tên học sinh: ……….....………………………………………………Lớp: 8/ …..

Điểm
Nhận xét của thầy cô giáo




 ĐỀ RA VÀ BÀI LÀM
A. LÝ THUYẾT( 2điểm): Chọn 1 trong 2 câu
Câu 1: Hãy phát biểu hệ quả định lý Ta lét trong tam giác( Vẽ hình và ghi GT, KL minh hoạ).
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Câu 2: Phát biểu định nghĩa tam giác A’B’C’ đồng dạng với tam giác ABC.
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B. BÀI TẬP BẮT BUỘC(8điểm):
Câu 3(3đ): Cho tam giác ABC có AB = 5cm, AC = 6cm, BC = 7cm. Tia phân giác của gócBAC cắt cạnh Bc tại E. Tính các đoạn thẳng EB, EC.
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Câu 4(5đ): Cho (ABC vuông tại A (AC > AB) . Kẻ tia phân giác của góc B cắt AC tại E.
Từ C hạ đoạn thẳng CD vuông góc với tia phân giác BE ( D thuộc tia BE) .
a.Chứng minh (BAE đồng dạng với (CDE.
b.Chứng minh góc EBC bằng góc ECD.
c.Cho AB = 3 cm, AC = 4 cm . Tính EC
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