1.2

2.96

3. 13

4. Four

5.7 9 Special Rectangular Square Matrix

1 1 176

6. 12 yuan

7. 123cm

8. 16

9. 12 volumes, 23 volumes

10.49/ 100

Exercise 2

1.D

2.D

3.D

4.D

5.D

6.C

7.C

8.D

9.-2

10. 1/2

1 1.5. 1? 10^8

12.5

13.2/25

14. 1/4 =

15.-8/8

16. 1/6

17. 1 1 1/ 10

18.-3/ 10

19. 1

20. 10/2 1

2 1.①. All 8 seats, 5 cars ② all 4 seats, 9 cars ③ 1 seat, 4 seats, and the remaining 8 seats 8 seats.

7 seats with 4 seats 1 8 seats with 7 * 200+1 * 300 =1700a:1700 yuan 7 seats with 4 seats18 seats.

Exercise 3

1.A

2.D

3.A

4.A

5.B

6.C

7.B

8.D

9.A

10.A

1 1.(2a)？

12.6x-y y+z

13.5m-4

14.2/3

15. 1/9

16.6 or 5

17.4xy？ -xy+8y？ - 1 1x-8xy- 17y？

18. 18a- 18b-2

19.25

20.- 14 - 1 1 -5 -2 4 16

0 0.2 0.6 0.8 1.2 2

Exercise 4

1.C

2.C

3.C

4.C

5.A

6.C

7.D

8.A

9.2

10. 1/3

1 1.5

12. 1.2

13.8.4

14. 180 ,240, 480

15.-5/9

16.- 12

17.- 12/7

18.K=5/3 X= -29/5

19. 16 PCs/hour

20.K=0.6 K=2/3

Exercise 5

1.D

2.D

3.C

4.A

5.B

6.D

7.B

8.D

9. Omit 4 1 1

10.9 6 5 6 4 4

1 1. 18

12. Cone

13.2

six

five

14. Omit

15.6 9 5 8 12 6 8 13 7 10 15 7

16.z+x-2=y

Exercise 6

1.D

2.C

3.B

4.B

5.B

6.B

7.D

8.34 22 12 36 177/600 25? 5? 16?

9.60?

10.3

1 1.75

12.5

13.45

14. Parallel, because parallel lines parallel to the same plane are parallel to each other.

15. BM = 2cm Mn = 5cm.

16.40? 120? 120?

17. Omit

18. (1) FOB AOD

19. slightly 90?

Exercise 7

1.D

2.B

3.C

4.D

5.B

6.C

7.2.7

8.3a-2b

9.a cube +b? /2

10.0

1 1.25

12.90 45

13. 10

14.60 30

15.-8

16.2 1

17.S=a？ +b？ -[ 1/2(a+b)b+ 1/2a？ ]32.5 square centimeters

18.6 km/h

19.7 2.5

20. 13 2a-b

2 1.740 yuan has a level of 45.

There are 5 people in Class Two and 58 people.

Exercise 8

1.C

2.C

3.B

4.D

5.A

6.A

7.C

8.D

9. 1/5 -2

10.2

1 1. Cone

12.7

13.40

14. 12

15.7

16.3 45

17. 17 168

18.-7 3.5

19.45

20.34

21.7127/144 equals 507.

22. Schoolbag 92 yuan Walkman 360 yuan

23. Times Supermarket

24. 1 -2 -20

25.60? a piece of cake