Kiểm tra Đại số 8 chương III

Họ và tên : .. Kiểm tra chơng III
Lớp: ..
Điểm Lời phê của cô giáo
Đề bài :
Câu 1 (3 điểm) : Em hãy chọn câu trả lời đúng trong các đáp án A, B, C, D
1/ Hai phơng trình nào tơng đơng:
A. 4x + 3 = 0 và 4x
2
+ 3 = 0 B.
5
1
x = 0 và
5
1
x = x
C. x + 1 = x và x + 1 = x + 1 D. x
2
+ 3 = 0 và (x
2
+ 3).(x 5) = 0
2/ Phơng trình 3x + m = x -1 nhận x = -3 là nghiệm, m có giá trị bằng bao nhiêu?
A. 13 B. -13 C. 5 D. -5
Câu 2 (4 điểm) : Giải các phơng trình:
a/
3
32
+
x
+
2
23

+
x
= 2,5 x 1
b/
2
3

x
x
+
)5)(2(
52

+
xx
x
=
5

x
x
Câu 3 (3 điểm) : Một ngời đi xe đạp từ A đến B với vận tốc trung bình 15km/h. Lúc
về ngời đó chỉ đi với vận tốc trung bình 12km/h nên thời gian về nhiều hơn thời gian
đi là 45 phút. Tính độ dài quãng đờng AB.
Bài làm
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