Kiểm tra học kỳ I – Trường thcs Đông Hà môn: Toán 9

PHỊNG GD-ĐT ĐỨC LINH	 KIỂM TRA HỌC KỲ I – NĂM HỌC: 2015– 2016
TRƯỜNG THCS ĐƠNG HÀ	 Mơn : Tốn 9 –Thời gian 90 phút
Họ và tên.. Điểm	Lời phê của thầy (cô ) giáo
Lớp: 9.
Bài 1 (3 điểm ) . Thực hiện phép tính :
a) 	
b) 
c) 
Bài 2 (3 điểm )
Vẽ đồ thị của hai hàm số sau trên cùng một mặt phẳng tọa độ
 (d1): y = -2x + 3 và (d2): y = -x + 4
Tìm tọa độ giao điểm hai đồ thị (d1) và (d2) bằng phép tính.
Tìm m để đồ thị hàm số (d1);(d2) và (d3): y = mx - 3 đồng quy.
Bài 3: (1 điểm ) Rút gọn biểu thức A = với a > 0 và a 16
Bài 4:(3 điểm ) Cho tam giác ABC vuơng tại A , đường cao AH. Vẽ đường trịn (A;AH). Từ B,C kẻ các tiếp tuyến BD; CE với đường trịn (D, E là các tiếp điểm khác H). Chứng minh rằng:
Bốn điểm B, D, A, H cùng thuộc một đường trịn.
BD + CE = BC
Ba điểm D, A, E thẳng hàng.
Tính diện tích tứ giác BDEC biết HC = 4cm; HB = 7cm.
Bài làm:
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