Đề kiểm tra chương 3 (Đại số 8) Thời gian 45phút Trường THCS Lờ Bỡnh

Trường THCS Lê Bình
Họ tên HS…………………………………..….
Lớp: 8B
 §Ò kiÓm tra ch­¬ng 3 (§¹i sè 8)
 Thêi gian 45phót



Điểm







M
Lời phê của thầy; cô

4
2
 
E
F
Caâu 1: (2,5 ñieåm) Cho bieát FE // NP, ME = 2cm, MF = 4cm,
8
FP = 8cm, tính ñoä daøi EN. 
P
N
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E
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6
Caâu 2: (2,5 ñieåm) Cho hình veõ, bieát: 
4
EF laø tia phaân giaùc cuûa goùc E, 
EM = 4cm, EN = 6cm, MN = 5cm. Tính FM, FN. 
N
F
M
 C
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................................................................................................................................................. Caâu 3: (3,5 ñieåm). Cho tam gi¸c ABC vu«ng t¹i A. Mét ®­êng th¼ng song song víi BC c¾t AB vµ AC theo thø tù t¹i M vµ N, ®­êng th¼ng ®i qua N vµ song song víi víi AB c¾t BC t¹i D. Cho biÕt AM = 6 cm; AN = 8 cm, BM = 4 cm. 
	a) TÝnh ®é dµi c¸c ®o¹n th¼ng MN, NC vµ BC. 
	b) Chøng minh: AB.CD = ND.CB
	c) TÝnh 
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Caâu 4 : (2,5 ñieåm) Cho hình thang ABCD (AB//CD), hai ñöôøng cheùo caét nhau taïi O.
Ñöôøng thaúng qua O song song vôùi hai ñaùy hình thang caét AD, BC laàn löôït taïi P, Q. 
Chöùng minh: 
S
a, DOAB DOCD 
b, OP = OQ
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Trường THCS Lê Bình
Họ tên HS…………………………………..….
Lớp: 8B
 §Ò kiÓm tra ch­¬ng 3(§¹i sè 8)
 Thêi gian 45phót



Điểm







Lời phê của thầy; cô
A

E
4
2
D
Caâu 1: (2.5 ñieåm) Cho bieát DE // BC, AD =2cm, 
6
AE = 4cm, EC = 6cm. Tính ñoä daøi DB.
B
C
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..................................................................................................
.................................................................................................................................................
E
.................................................................................................................................................
8
 
12
Caâu 2: (2.5 ñieåm) Cho hình veõ, bieát: 
EF laø tia phaân giaùc cuûa goùc E,
N
F
M
EM = 8cm, EN = 12cm, MN = 11cm. 
Tính FM, FN.
 ................................................................................................................................................. ...............................................................................................................................................................................................................................................................................................................................................................................................................................................................Caâu 3: (3.5 ñieåm). Cho tam gi¸c ABC vu«ng t¹i A. Mét ®­êng th¼ng song song víi BC c¾t AB vµ AC theo thø tù t¹i M vµ N, ®­êng th¼ng ®i qua N vµ song song víi víi AB c¾t BC t¹i D. Cho biÕt AM = 3 cm; AN = 4 cm, BM = 2 cm. 
	a) TÝnh ®é dµi c¸c ®o¹n th¼ng MN, NC vµ BC. 
	b) Chøng minh: AB.CD = ND.AB
	c) TÝnh 
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Caâu 4 : (2,5 ñieåm) Cho hình thang ABCD (AB//CD), hai ñöôøng cheùo caét nhau taïi I.
Ñöôøng thaúng qua I song song vôùi hai ñaùy hình thang caét AD, BC laàn löôït taïi M, N. 
Chöùng minh: 
S
a, DIAB DICD 
b, IM = IN.
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